1
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Gomez A, Thompson WH, Laage D. Neural-network-based molecular dynamics simulations reveal that proton transport in water is doubly gated by sequential hydrogen-bond exchange. Nat Chem 2024:10.1038/s41557-024-01593-y. [PMID: 39164581 DOI: 10.1038/s41557-024-01593-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/03/2024] [Indexed: 08/22/2024]
Abstract
The transport of excess protons in water is central to acid-base chemistry, biochemistry and energy production. However, elucidating its mechanism has been challenging. Recent nonlinear vibrational spectroscopy experiments could not be explained by existing models. Here we use both vibrational spectroscopy calculations and neural-network-based molecular dynamics simulations that account for nuclear quantum effects for all atoms to determine the proton transport mechanism. Our simulations reveal an equilibrium between two stable proton-localized structures with distinct Eigen-like and Zundel-like hydrogen-bond motifs. Proton transport follows a three-step mechanism gated by two successive hydrogen-bond exchanges: the first reduces the proton-acceptor water coordination, leading to proton transfer, and the second, the rate-limiting step, prevents rapid back-transfer by increasing the proton-donor coordination. This sequential mechanism is consistent with experimental characterizations of proton diffusion, explaining the low activation energy and the prolonged intermediate lifetimes in vibrational spectroscopy. These results are crucial for understanding proton dynamics in biochemical and technological systems.
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Affiliation(s)
- Axel Gomez
- PASTEUR, Department of Chemistry, École normale supérieure, PSL University, Sorbonne Université, CNRS, Paris, France
| | - Ward H Thompson
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Damien Laage
- PASTEUR, Department of Chemistry, École normale supérieure, PSL University, Sorbonne Université, CNRS, Paris, France.
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2
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Zheng W, He L, Tang T, Ren R, Lee H, Ding G, Wang L, Sun L. Poly(Dibenzothiophene-Terphenyl Piperidinium) for High-Performance Anion Exchange Membrane Water Electrolysis. Angew Chem Int Ed Engl 2024; 63:e202405738. [PMID: 38850230 DOI: 10.1002/anie.202405738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 06/01/2024] [Accepted: 06/06/2024] [Indexed: 06/10/2024]
Abstract
The anion exchange membrane water electrolysis is widely regarded as the next-generation technology for producing green hydrogen. The OH- conductivity of the anion exchange membrane plays a key role in the practical implementation of this device. Here, we present a series of Z-S-x membranes with dibenzothiophene groups. These membranes contain sulfur-enhanced hydrogen bond networks that link surrounding surface site hopping regions, forming continuous OH- conducting highways. Z-S-20 has a high through-plane OH- conductivity of 182±28 mS cm-1 and ultralong stability of 2650 h in KOH solution at 80 °C. Based on rational design, we achieved a high PGM-free alkaline water electrolysis performance of 7.12 A cm-2 at 2.0 V in a flow cell and demonstrated durability of 650 h at 2 A cm-2 at 40 °C with a cell voltage increase of 0.65 mV/h.
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Affiliation(s)
- Wentao Zheng
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Department of Chemistry, Zhejiang University, 310058, Hangzhou, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Lanlan He
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Tang Tang
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Rong Ren
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Husileng Lee
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Guoheng Ding
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Linqin Wang
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| | - Licheng Sun
- Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
- Division of Solar Energy Conversion and Catalysis at Westlake University, Zhejiang Baima Lake Laboratory Co., Ltd., Hangzhou, 310000, Zhejiang Province, China
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3
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Hino K, Kurashige Y. Encoding a Many-Body Potential Energy Surface into a Grid-Based Matrix Product Operator. J Chem Theory Comput 2024; 20:3839-3849. [PMID: 38647101 DOI: 10.1021/acs.jctc.4c00046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
An efficient algorithm for compressing a given many-body potential energy surface (PES) of molecular systems into a grid-based matrix product operator (MPO) is proposed. The PES is once represented by a full-dimensional or truncated many-body expansion form, which is obtained by ab initio calculations at each grid mesh point, and then all terms in the expansion are compressed and merged into a single MPO while maintaining the bond dimension of the MPO as small as possible. It was shown that the ab initio PES of the H2CO was compressed by more than 2 orders of magnitude in the size of the site operators without loss of accuracy. By the use of grid basis, the tensor rank of the site operators of the MPO is reduced from four to three due to the diagonal nature of the position-dependent operators on grid basis, which significantly reduces the computational cost of the tensor contractions required in the real and imaginary time evolution of the matrix product state (MPS) wave functions with the grid-based MPO (Grid-MPO) Hamiltonian. Similar to other grid-based methods, Grid-MPO is easily applicable to any kinds of potentials of molecular systems, such as analytical empirical model potentials expressed by position operators and ab initio potentials, if the values at the grid points are available. Using the Grid-MPO combined with the MPS, we calculated the time correlation function of the Eigen cation H 3 O + ( H 2 O ) 3 to predict the infrared spectrum and compared with the experimental and the previous theoretical studies. The actual scaling with the size of systems was examined for the multidimensional Henon-Heiles Hamiltonian. It was shown that the method is considerably accelerated by the graphic processing unit (GPU) because the sizes of site operators were kept small and all tensors were able to be stored on the VRAM of a GPU.
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Affiliation(s)
- Kentaro Hino
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yuki Kurashige
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
- FOREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
- CREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
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4
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Habibi P, Polat HM, Blazquez S, Vega C, Dey P, Vlugt TJH, Moultos OA. Accurate Free Energies of Aqueous Electrolyte Solutions from Molecular Simulations with Non-polarizable Force Fields. J Phys Chem Lett 2024; 15:4477-4485. [PMID: 38634502 PMCID: PMC11057036 DOI: 10.1021/acs.jpclett.4c00428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/19/2024]
Abstract
Non-polarizable force fields fail to accurately predict free energies of aqueous electrolytes without compromising the predictive ability for densities and transport properties. A new approach is presented in which (1) TIP4P/2005 water and scaled charge force fields are used to describe the interactions in the liquid phase and (2) an additional Effective Charge Surface (ECS) is used to compute free energies at zero additional computational expense. The ECS is obtained using a single temperature-independent charge scaling parameter per species. Thereby, the chemical potential of water and the free energies of hydration of various aqueous salts (e.g., NaCl and LiCl) are accurately described (deviations less than 5% from experiments), in sharp contrast to calculations where the ECS is omitted (deviations larger than 20%). This approach enables accurate predictions of free energies of aqueous electrolyte solutions using non-polarizable force fields, without compromising liquid-phase properties.
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Affiliation(s)
- Parsa Habibi
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical
Engineering, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft, Netherlands
- Department
of Materials Science and Engineering, Faculty of Mechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, Netherlands
| | - H. Mert Polat
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical
Engineering, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft, Netherlands
| | - Samuel Blazquez
- Departamento
de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Carlos Vega
- Departamento
de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Poulumi Dey
- Department
of Materials Science and Engineering, Faculty of Mechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, Netherlands
| | - Thijs J. H. Vlugt
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical
Engineering, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft, Netherlands
| | - Othonas A. Moultos
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical
Engineering, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft, Netherlands
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5
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Thorat A, Chauhan R, Sartape R, Singh MR, Shah JK. Effect of K + Force Fields on Ionic Conductivity and Charge Dynamics of KOH in Ethylene Glycol. J Phys Chem B 2024; 128:3707-3719. [PMID: 38572661 PMCID: PMC11033864 DOI: 10.1021/acs.jpcb.3c08480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/05/2024]
Abstract
Predicting ionic conductivity is crucial for developing efficient electrolytes for energy storage and conversion and other electrochemical applications. An accurate estimate of ionic conductivity requires understanding complex ion-ion and ion-solvent interactions governing the charge transport at the molecular level. Molecular simulations can provide key insights into the spatial and temporal behavior of electrolyte constituents. However, such insights depend on the ability of force fields to describe the underlying phenomena. In this work, molecular dynamics simulations were leveraged to delineate the impact of force field parameters on ionic conductivity predictions of potassium hydroxide (KOH) in ethylene glycol (EG). Four different force fields were used to represent the K+ ion. Diffusion-based Nernst-Einstein and correlation-based Einstein approaches were implemented to estimate the ionic conductivity, and the predicted values were compared with experimental measurements. The physical aspects, including ion-aggregation, charge distribution, cluster correlation, and cluster dynamics, were also examined. A force field was identified that provides reasonably accurate Einstein conductivity values and a physically coherent representation of the electrolyte at the molecular level.
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Affiliation(s)
- Amey Thorat
- School
of Chemical Engineering, Oklahoma State
University, Stillwater, Oklahoma 74078, United States
| | - Rohit Chauhan
- Department
of Chemical Engineering, University of Illinois
at Chicago, Chicago, Illinois 60608, United States
| | - Rohan Sartape
- Department
of Chemical Engineering, University of Illinois
at Chicago, Chicago, Illinois 60608, United States
| | - Meenesh R. Singh
- Department
of Chemical Engineering, University of Illinois
at Chicago, Chicago, Illinois 60608, United States
| | - Jindal K. Shah
- School
of Chemical Engineering, Oklahoma State
University, Stillwater, Oklahoma 74078, United States
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6
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Zhang Q, Chen Q, Shaik S, Wang B. Flavin-N5OOH Functions as both a Powerful Nucleophile and a Base in the Superfamily of Flavoenzymes. Angew Chem Int Ed Engl 2024; 63:e202318629. [PMID: 38299700 DOI: 10.1002/anie.202318629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/30/2024] [Accepted: 01/31/2024] [Indexed: 02/02/2024]
Abstract
Flavoenzymes can mediate a large variety of oxidation reactions through the activation of oxygen. However, the O2 activation chemistry of flavin enzymes is not yet fully exploited. Normally, the O2 activation occurs at the C4a site of the flavin cofactor, yielding the flavin C4a-(hydro)hydroperoxyl species in monooxygenases or oxidases. Using extensive MD simulations, QM/MM calculations and QM calculations, our studies reveal the formation of the common nucleophilic species, Flavin-N5OOH, in two distinct flavoenzymes (RutA and EncM). Our studies show that Flavin-N5OOH acts as a powerful nucleophile that promotes C-N cleavage of uracil in RutA, and a powerful base in the deprotonation of substrates in EncM. We reason that Flavin-N5OOH can be a common reactive species in the superfamily of flavoenzymes, which accomplish generally selective general base catalysis and C-X (X=N, S, Cl, O) cleavage reactions that are otherwise challenging with solvated hydroxide ion base. These results expand our understanding of the chemistry and catalysis of flavoenzymes.
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Affiliation(s)
- Qiaoyu Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Qianqian Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Sason Shaik
- Institute of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
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7
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Arandhara M, Ramesh SG. Nuclear Quantum Effects in Hydroxide Hydrate Along the H-Bond Bifurcation Pathway. J Phys Chem A 2024; 128:1600-1610. [PMID: 38393819 DOI: 10.1021/acs.jpca.3c08027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2024]
Abstract
Path integral (PI) simulations are used to explore nuclear quantum effects (NQEs) in hydroxide hydrate and its perdeuterated isotopomer along the H-bond bifurcation pathway. Toward this, a new potential energy surface using the symmetric gradient domain machine learning method with ab initio data at the CCSD(T)/aug-cc-pVTZ level is built. From PI umbrella sampling (US) simulations, free energy profiles along the bifurcation coordinate are explored as a function of temperature. At ambient temperature, the bifurcation barrier is increased upon inclusion of NQEs. At low temperatures in the deep tunneling regime, the barrier is strongly decreased and flattened. These trends are examined, and the role of the O-O distance is also investigated through two-dimensional US simulations.
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Affiliation(s)
- Mrinal Arandhara
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sai G Ramesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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8
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DeCoursey TE. Transcendent Aspects of Proton Channels. Annu Rev Physiol 2024; 86:357-377. [PMID: 37931166 PMCID: PMC10938948 DOI: 10.1146/annurev-physiol-042222-023242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
A handful of biological proton-selective ion channels exist. Some open at positive or negative membrane potentials, others open at low or high pH, and some are light activated. This review focuses on common features that result from the unique properties of protons. Proton conduction through water or proteins differs qualitatively from that of all other ions. Extraordinary proton selectivity is needed to ensure that protons permeate and other ions do not. Proton selectivity arises from a proton pathway comprising a hydrogen-bonded chain that typically includes at least one titratable amino acid side chain. The enormously diverse functions of proton channels in disparate regions of the phylogenetic tree can be summarized by considering the chemical and electrical consequences of proton flux across membranes. This review discusses examples of cells in which proton efflux serves to increase pHi, decrease pHo, control the membrane potential, generate action potentials, or compensate transmembrane movement of electrical charge.
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Affiliation(s)
- Thomas E DeCoursey
- Department of Physiology & Biophysics, Rush University, Chicago, Illinois, USA;
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9
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Mandal I, Karimova NV, Zakai I, Gerber RB. Formation of Chlorine in the Atmosphere by Reaction of Hypochlorous Acid with Seawater. J Phys Chem Lett 2024; 15:432-438. [PMID: 38189241 PMCID: PMC11139381 DOI: 10.1021/acs.jpclett.3c03035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/16/2023] [Accepted: 12/20/2023] [Indexed: 01/09/2024]
Abstract
The highly reactive dihalogens play a significant role in the oxidative chemistry of the troposphere. One of the main reservoirs of these halogens is hypohalous acids, HOX, which produce dihalogens in the presence of halides (Y-), where X, Y = Cl, Br, I. These reactions occur in and on aerosol particles and seawater surfaces and have been studied experimentally and by field observations. However, the mechanisms of these atmospheric reactions are still unknown. Here, we establish the atomistic mechanism of HOCl + Cl- → Cl2 + OH- at the surface of the water slab by performing ab initio molecular dynamics (AIMD) simulations. Main findings are (1) This reaction proceeds by halogen-bonded complexes of (HOCl)···(Cl-)aq surrounded with the neighboring water molecules. (2) The halogen bonded (HOCl)···(Cl-)aq complexes undergo charge transfer from Cl- to OH- to form transient Cl2 at neutral pH. (3) The addition of a proton to one proximal water greatly facilitates the Cl2 formation, which explains the enhanced rate at low pH.
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Affiliation(s)
- Imon Mandal
- The
Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Natalia V. Karimova
- Department
of Chemistry, University of California, Irvine, California 92697, United States
| | - Itai Zakai
- The
Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - R. Benny Gerber
- The
Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- Department
of Chemistry, University of California, Irvine, California 92697, United States
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10
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Iyengar SS, Zhang JH, Saha D, Ricard TC. Graph-| Q⟩⟨ C|: A Quantum Algorithm with Reduced Quantum Circuit Depth for Electronic Structure. J Phys Chem A 2023; 127:9334-9345. [PMID: 37906738 DOI: 10.1021/acs.jpca.3c04261] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
The accurate determination of chemical properties is known to have a critical impact on multiple fundamental chemical problems but is deeply hindered by the steep algebraic scaling of electron correlation calculations and the exponential scaling of quantum nuclear dynamics. With the advent of new quantum computing hardware and associated developments in creating new paradigms for quantum software, this avenue has been recognized as perhaps one way to address exponentially complex challenges in quantum chemistry and molecular dynamics. In this paper, we discuss a new approach to drastically reduce the quantum circuit depth (by several orders of magnitude) and help improve the accuracy in the quantum computation of electron correlation energies for large molecular systems. The method is derived from a graph-theoretic approach to molecular fragmentation and enables us to create a family of projection operators that decompose quantum circuits into separate unitary processes. Some of these processes can be treated on quantum hardware and others on classical hardware in a completely asynchronous and parallel fashion. Numerical benchmarks are provided through the computation of unitary coupled-cluster singles and doubles (UCCSD) energies for medium-sized protonated and neutral water clusters using the new quantum algorithms presented here.
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Affiliation(s)
- Srinivasan S Iyengar
- Department of Chemistry, Department of Physics, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Juncheng Harry Zhang
- Department of Chemistry, Department of Physics, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Debadrita Saha
- Department of Chemistry, Department of Physics, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Timothy C Ricard
- Department of Chemistry, Department of Physics, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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11
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Petrus E, Garay-Ruiz D, Reiher M, Bo C. Multi-Time-Scale Simulation of Complex Reactive Mixtures: How Do Polyoxometalates Form? J Am Chem Soc 2023; 145:18920-18930. [PMID: 37496164 DOI: 10.1021/jacs.3c05514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Understanding the dynamics of reactive mixtures still challenges both experiments and theory. A relevant example can be found in the chemistry of molecular metal-oxide nanoclusters, also known as polyoxometalates. The high number of species potentially involved, the interconnectivity of the reaction network, and the precise control of the pH and concentrations needed in the synthesis of such species make the theoretical/computational treatment of such processes cumbersome. This work addresses this issue relying on a unique combination of recently developed computational methods that tackle the construction, kinetic simulation, and analysis of complex chemical reaction networks. By using the Bell-Evans-Polanyi approximation for estimating activation energies, and an accurate and robust linear scaling for correcting the computed pKa values, we report herein multi-time-scale kinetic simulations for the self-assembly processes of polyoxotungstates that comprise 22 orders of magnitude, from tens of femtoseconds to months of reaction time. This very large time span was required to reproduce very fast processes such as the acid/base equilibria (at 10-12 s), relatively slow reactions such as the formation of key clusters such as the metatungstate (at 103 s), and the very slow assembly of the decatungstate (at 106 s). Analysis of the kinetic data and of the reaction network topology shed light onto the details of the main reaction mechanisms, which explains the origin of kinetic and thermodynamic control followed by the reaction. Simulations at alkaline pH fully reproduce experimental evidence since clusters do not form under those conditions.
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Affiliation(s)
- Enric Petrus
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avenida Països Catalans, 16, Tarragona 43007, Spain
| | - Diego Garay-Ruiz
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avenida Països Catalans, 16, Tarragona 43007, Spain
| | - Markus Reiher
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, Zürich 8093, Switzerland
| | - Carles Bo
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Avenida Països Catalans, 16, Tarragona 43007, Spain
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel•li Domingo s/n, Tarragona 43007, Spain
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12
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Atsango AO, Morawietz T, Marsalek O, Markland TE. Developing machine-learned potentials to simultaneously capture the dynamics of excess protons and hydroxide ions in classical and path integral simulations. J Chem Phys 2023; 159:074101. [PMID: 37581418 DOI: 10.1063/5.0162066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 07/31/2023] [Indexed: 08/16/2023] Open
Abstract
The transport of excess protons and hydroxide ions in water underlies numerous important chemical and biological processes. Accurately simulating the associated transport mechanisms ideally requires utilizing ab initio molecular dynamics simulations to model the bond breaking and formation involved in proton transfer and path-integral simulations to model the nuclear quantum effects relevant to light hydrogen atoms. These requirements result in a prohibitive computational cost, especially at the time and length scales needed to converge proton transport properties. Here, we present machine-learned potentials (MLPs) that can model both excess protons and hydroxide ions at the generalized gradient approximation and hybrid density functional theory levels of accuracy and use them to perform multiple nanoseconds of both classical and path-integral proton defect simulations at a fraction of the cost of the corresponding ab initio simulations. We show that the MLPs are able to reproduce ab initio trends and converge properties such as the diffusion coefficients of both excess protons and hydroxide ions. We use our multi-nanosecond simulations, which allow us to monitor large numbers of proton transfer events, to analyze the role of hypercoordination in the transport mechanism of the hydroxide ion and provide further evidence for the asymmetry in diffusion between excess protons and hydroxide ions.
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Affiliation(s)
- Austin O Atsango
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Tobias Morawietz
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Ondrej Marsalek
- Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
| | - Thomas E Markland
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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13
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Codescu MA, Kunze T, Weiß M, Brehm M, Kornilov O, Sebastiani D, Nibbering ETJ. Ultrafast Proton Transfer Pathways Mediated by Amphoteric Imidazole. J Phys Chem Lett 2023; 14:4775-4785. [PMID: 37186569 DOI: 10.1021/acs.jpclett.3c00595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Imidazole, being an amphoteric molecule, can act both as an acid and as a base. This property enables imidazole, as an essential building block, to effectively facilitate proton transport in high-temperature proton exchange membrane fuel cells and in proton channel transmembrane proteins, enabling those systems to exhibit high energy conversion yields and optimal biological function. We explore the amphoteric properties of imidazole by following the proton transfer exchange reaction dynamics with the bifunctional photoacid 7-hydroxyquinoline (7HQ). We show with ultrafast ultraviolet-mid-infrared pump-probe spectroscopy how for imidazole, in contrast to expectations based on textbook knowledge of acid-base reactivity, the preferential reaction pathway is that of an initial proton transfer from 7HQ to imidazole, and only at a later stage a transfer from imidazole to 7HQ, completing the 7HQ tautomerization reaction. An assessment of the molecular distribution functions and first-principles calculations of proton transfer reaction barriers reveal the underlying reasons for our observations.
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Affiliation(s)
- Marius-Andrei Codescu
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany
| | - Thomas Kunze
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Moritz Weiß
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Oleg Kornilov
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany
| | - Daniel Sebastiani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Erik T J Nibbering
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany
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14
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Wang L, Yan J, Hong Y, Yu Z, Chen J, Zheng J. Ultrahigh-rate and ultralong-life aqueous batteries enabled by special pair-dancing proton transfer. SCIENCE ADVANCES 2023; 9:eadf4589. [PMID: 37146149 PMCID: PMC10162668 DOI: 10.1126/sciadv.adf4589] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The design of Faradaic battery electrodes with high rate capability and long cycle life comparable to those of supercapacitors is a grand challenge. Here, we bridge this performance gap by taking advantage of a unique ultrafast proton conduction mechanism in vanadium oxide electrode, developing an aqueous battery with untrahigh rate capability up to 1000 C (400 A g-1) and extremely long life of 0.2 million cycles. The mechanism is elucidated by comprehensive experimental and theoretical results. Instead of slow individual Zn2+ transfer or Grotthuss chain transfer of confined H+, the ultrafast kinetics and excellent cyclic stability are enabled by rapid 3D proton transfer in vanadium oxide via the special pair dance switching between Eigen and Zundel configurations with little constraint and low energy barriers. This work provides insight into developing high-power and long-life electrochemical energy storage devices with nonmetal ion transfer through special pair dance topochemistry dictated by hydrogen bond.
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Affiliation(s)
- Lulu Wang
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Jie Yan
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Yuexian Hong
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Zhihao Yu
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Jitao Chen
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Junrong Zheng
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
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15
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Popov I, Zhu Z, Young-Gonzales AR, Sacci RL, Mamontov E, Gainaru C, Paddison SJ, Sokolov AP. Search for a Grotthuss mechanism through the observation of proton transfer. Commun Chem 2023; 6:77. [PMID: 37087505 PMCID: PMC10122652 DOI: 10.1038/s42004-023-00878-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 04/04/2023] [Indexed: 04/24/2023] Open
Abstract
The transport of protons is critical in a variety of bio- and electro-chemical processes and technologies. The Grotthuss mechanism is considered to be the most efficient proton transport mechanism, generally implying a transfer of protons between 'chains' of host molecules via elementary reactions within the hydrogen bonds. Although Grotthuss proposed this concept more than 200 years ago, only indirect experimental evidence of the mechanism has been observed. Here we report the first experimental observation of proton transfer between the molecules in pure and 85% aqueous phosphoric acid. Employing dielectric spectroscopy, quasielastic neutron, and light scattering, and ab initio molecular dynamic simulations we determined that protons move by surprisingly short jumps of only ~0.5-0.7 Å, much smaller than the typical ion jump length in ionic liquids. Our analysis confirms the existence of correlations in these proton jumps. However, these correlations actually reduce the conductivity, in contrast to a desirable enhancement, as is usually assumed by a Grotthuss mechanism. Furthermore, our analysis suggests that the expected Grotthuss-like enhancement of conductivity cannot be realized in bulk liquids where ionic correlations always decrease conductivity.
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Affiliation(s)
- Ivan Popov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
- Department of Chemistry, University of Tennessee, Knoxville, TN, USA
| | - Zhenghao Zhu
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN, USA
| | | | - Robert L Sacci
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Eugene Mamontov
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Catalin Gainaru
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Stephen J Paddison
- Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN, USA.
| | - Alexei P Sokolov
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
- Department of Chemistry, University of Tennessee, Knoxville, TN, USA.
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16
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Zhang M, Hua H, Dai P, He Z, Han L, Tang P, Yang J, Lin P, Zhang Y, Zhan D, Chen J, Qiao Y, Li CC, Zhao J, Yang Y. Dynamically Interfacial pH-Buffering Effect Enabled by N-Methylimidazole Molecules as Spontaneous Proton Pumps toward Highly Reversible Zinc-Metal Anodes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208630. [PMID: 36739482 DOI: 10.1002/adma.202208630] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/04/2022] [Indexed: 06/18/2023]
Abstract
Aqueous zinc-metal batteries have attracted extensive attention due to their outstanding merits of high safety and low cost. However, the intrinsic thermodynamic instability of zinc in aqueous electrolyte inevitably results in hydrogen evolution, and the consequent generation of OH- at the interface will dramatically exacerbate the formation of dead zinc and dendrites. Herein, a dynamically interfacial pH-buffering strategy implemented by N-methylimidazole (NMI) additive is proposed to remove the detrimental OH- at zinc/electrolyte interface in real-time, thus eliminating the accumulation of by-products fundamentally. Electrochemical quartz crystal microbalance and molecular dynamics simulation results reveal the existence of an interfacial absorption layer assembled by NMI and protonated NMI (NMIH+ ), which acts as an ion pump for replenishing the interface with protons constantly. Moreover, an in situ interfacial pH detection method with micro-sized spatial resolution based on the ultra-microelectrode technology is developed to probe the pH evolution in diffusion layer, confirming the stabilized interfacial chemical environment in NMI-containing electrolyte. Accordingly, with the existence of NMI, an excellent cumulative plating capacity of 4.2 Ah cm-2 and ultrahigh Coulombic efficiency of 99.74% are realized for zinc electrodes. Meanwhile, the NMI/NMIH+ buffer additive can accelerate the dissolution/deposition process of MnO2 /Mn2+ on the cathode, leading to enhanced cycling capacity.
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Affiliation(s)
- Minghao Zhang
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Haiming Hua
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Pengpeng Dai
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Zheng He
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Lianhuan Han
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Peiwen Tang
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Jin Yang
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Pengxiang Lin
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Yufei Zhang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China
| | - Dongping Zhan
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Jianken Chen
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Yu Qiao
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Cheng Chao Li
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, P. R. China
| | - Jinbao Zhao
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
| | - Yang Yang
- State Key Lab of Physical Chemistry of Solid Surfaces, State-Province Joint Engineering Laboratory of Power Source Technology for New Energy Vehicle, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, P. R. China
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17
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Bandyopadhyay D, Bhanja K, Choudhury N. On the Propensity of Excess Hydroxide Ions at the Alcohol Monolayer-Water Interface. J Phys Chem B 2023; 127:783-793. [PMID: 36639623 DOI: 10.1021/acs.jpcb.2c05719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Atomistic molecular dynamics simulations have been employed to study the self-ion (H+ and OH-) distribution at the interface between long-chain C16-OH alcohol (cetyl alcohol) monolayer and water. It is well known that the free air-water interface is acidic due to accumulation of the hydronium (H3O+) ions at the interface. In the present study, we have observed that contrary to the air-water interface, at the long-chain alcohol monolayer-water interface, it is the hydroxide (OH-) ion, not the hydronium ion (H3O+) that gets accumulated. By calculating the potential of mean forces, it is confirmed that there is extra stabilization for the OH- ions at the interface relative to the bulk, but no such stabilization is observed for the H3O+ ions. By analyzing the interaction of the self-ions with other constituents in the medium, it is clearly shown that the favorable interaction of the OH- ions with the alcoholic -OH groups stabilizes this ion at the interface. By calculating coordination numbers of the self-ions it is observed that around 50% water neighbors are substituted by alcoholic -OH in case of the hydroxide ion at the interface, whereas in the case of hydronium ions, only 15% water neighbors are substituted by the alcoholic -OH. The most interesting observation about the local structure and H-bonding pattern is that the hydroxide ion acts solely as the H-bond acceptor, but the hydronium ion acts only as the H-bond donor.
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Affiliation(s)
| | - Kalyan Bhanja
- Heavy Water Division, Bhabha Atomic Research Centre, Mumbai400 085, India
| | - Niharendu Choudhury
- Theoretical Chemistry Section, Chemistry Division, Bhabha Atomic Research Centre, Mumbai400 085, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai400 094, India
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18
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Yan S, Wang B, Lin H. Tracking the Delocalized Proton in Concerted Proton Transfer in Bulk Water. J Chem Theory Comput 2023; 19:448-459. [PMID: 36630655 DOI: 10.1021/acs.jctc.2c01097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A solvated proton in water is often characterized as a charge or structural defect, and it is important to track its evolution on-the-fly in certain dynamics simulations. Previously, we introduced the proton indicator, a pseudo-atom, whose position approximates the location of the excess proton modeled as a structural defect. The proton indicator generally yields a smooth trajectory of a hydrated proton diffusing in aqueous solutions, including in the events of stepwise proton transfer via the Grotthuss mechanism; however, the proton indicator did not perform well in the events of concerted proton transfer, for which it occasionally yielded large position displacements between two successive time steps. To overcome this hurdle, we develop a new algorithm of a proton indicator with greatly enhanced performance for concerted proton transfer in bulk water. A protocol is proposed to exhaustively explore the hydrogen-bonding network of the water wires over which the excess proton is delocalized and to properly account for the contributions of the water molecules in this network as the geometry evolves. The new proton indicator (called Indicator 2.0) is assessed in dynamics simulations of an excess proton in bulk water and in specially constructed model systems of more complex architectures. The results demonstrate that the new indicator yields a smooth trajectory in both stepwise and concerted proton transfers.
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Affiliation(s)
- Shengheng Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen360015P. R. China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen360015P. R. China
| | - Hai Lin
- Department of Chemistry, CB 194, University of Colorado Denver, P.O. Box 173364, Denver, Colorado80217, United States
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19
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Abstract
Adsorption energy (AE) of reactive intermediate is currently the most important descriptor for electrochemical reactions (e.g., water electrolysis, hydrogen fuel cell, electrochemical nitrogen fixation, electrochemical carbon dioxide reduction, etc.), which can bridge the gap between catalyst's structure and activity. Tracing the history and evolution of AE can help to understand electrocatalysis and design optimal electrocatalysts. Focusing on oxygen electrocatalysis, this review aims to provide a comprehensive introduction on how AE is selected as the activity descriptor, the intrinsic and empirical relationships related to AE, how AE links the structure and electrocatalytic performance, the approaches to obtain AE, the strategies to improve catalytic activity by modulating AE, the extrinsic influences on AE from the environment, and the methods in circumventing linear scaling relations of AE. An outlook is provided at the end with emphasis on possible future investigation related to the obstacles existing between adsorption energy and electrocatalytic performance.
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Affiliation(s)
- Junming Zhang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Hong Bin Yang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Daojin Zhou
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, P. R. China.,Department of Electrical and Computer Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario M5S 1A4, Canada
| | - Bin Liu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
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20
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Kumar A, DeGregorio N, Ricard T, Iyengar SS. Graph-Theoretic Molecular Fragmentation for Potential Surfaces Leads Naturally to a Tensor Network Form and Allows Accurate and Efficient Quantum Nuclear Dynamics. J Chem Theory Comput 2022; 18:7243-7259. [PMID: 36332133 DOI: 10.1021/acs.jctc.2c00484] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Molecular fragmentation methods have revolutionized quantum chemistry. Here, we use a graph-theoretically generated molecular fragmentation method, to obtain accurate and efficient representations for multidimensional potential energy surfaces and the quantum time-evolution operator, which plays a critical role in quantum chemical dynamics. In doing so, we find that the graph-theoretic fragmentation approach naturally reduces the potential portion of the time-evolution operator into a tensor network that contains a stream of coupled lower-dimensional propagation steps to potentially achieve quantum dynamics with reduced complexity. Furthermore, the fragmentation approach used here has previously been shown to allow accurate and efficient computation of post-Hartree-Fock electronic potential energy surfaces, which in many cases has been shown to be at density functional theory cost. Thus, by combining the advantages of molecular fragmentation with the tensor network formalism, the approach yields an on-the-fly quantum dynamics scheme where both the electronic potential calculation and nuclear propagation portion are enormously simplified through a single stroke. The method is demonstrated by computing approximations to the propagator and to potential surfaces for a set of coupled nuclear dimensions within a protonated water wire problem exhibiting the Grotthuss mechanism of proton transport. In all cases, our approach has been shown to reduce the complexity of representing the quantum propagator, and by extension action of the propagator on an initial wavepacket, by several orders, with minimal loss in accuracy.
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Affiliation(s)
- Anup Kumar
- Department of Chemistry, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Nicole DeGregorio
- Department of Chemistry, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Timothy Ricard
- Department of Chemistry, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
| | - Srinivasan S Iyengar
- Department of Chemistry, and the Indiana University Quantum Science and Engineering Center (IU-QSEC), Indiana University, Bloomington, Indiana 47405, United States
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21
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Chen Y, Lu Z, Chen T, Liu Y, Han G, Xu G. Template-free hydrothermal synthesis of δ-MnO2 hierarchical nanoflowers with potassium ions intercalation as cathodes for high-performing aqueous zinc ion batteries. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.117084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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22
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Habibi P, Rahbari A, Blazquez S, Vega C, Dey P, Vlugt TJH, Moultos OA. A New Force Field for OH - for Computing Thermodynamic and Transport Properties of H 2 and O 2 in Aqueous NaOH and KOH Solutions. J Phys Chem B 2022; 126:9376-9387. [PMID: 36325986 PMCID: PMC9677430 DOI: 10.1021/acs.jpcb.2c06381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/20/2022] [Indexed: 11/05/2022]
Abstract
The thermophysical properties of aqueous electrolyte solutions are of interest for applications such as water electrolyzers and fuel cells. Molecular dynamics (MD) and continuous fractional component Monte Carlo (CFCMC) simulations are used to calculate densities, transport properties (i.e., self-diffusivities and dynamic viscosities), and solubilities of H2 and O2 in aqueous sodium and potassium hydroxide (NaOH and KOH) solutions for a wide electrolyte concentration range (0-8 mol/kg). Simulations are carried out for a temperature and pressure range of 298-353 K and 1-100 bar, respectively. The TIP4P/2005 water model is used in combination with a newly parametrized OH- force field for NaOH and KOH. The computed dynamic viscosities at 298 K for NaOH and KOH solutions are within 5% from the reported experimental data up to an electrolyte concentration of 6 mol/kg. For most of the thermodynamic conditions (especially at high concentrations, pressures, and temperatures) experimental data are largely lacking. We present an extensive collection of new data and engineering equations for H2 and O2 self-diffusivities and solubilities in NaOH and KOH solutions, which can be used for process design and optimization of efficient alkaline electrolyzers and fuel cells.
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Affiliation(s)
- Parsa Habibi
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical,
Maritime and Materials Engineering, Delft
University of Technology, Leeghwaterstraat 39, 2628 CBDelft, The Netherlands
- Department
of Materials Science and Engineering, Faculty of Mechanical, Maritime
and Materials Engineering, Delft University
of Technology, Mekelweg
2, 2628 CDDelft, The Netherlands
| | - Ahmadreza Rahbari
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical,
Maritime and Materials Engineering, Delft
University of Technology, Leeghwaterstraat 39, 2628 CBDelft, The Netherlands
| | - Samuel Blazquez
- Depto.
Química Física, Fac. Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
| | - Carlos Vega
- Depto.
Química Física, Fac. Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
| | - Poulumi Dey
- Department
of Materials Science and Engineering, Faculty of Mechanical, Maritime
and Materials Engineering, Delft University
of Technology, Mekelweg
2, 2628 CDDelft, The Netherlands
| | - Thijs J. H. Vlugt
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical,
Maritime and Materials Engineering, Delft
University of Technology, Leeghwaterstraat 39, 2628 CBDelft, The Netherlands
| | - Othonas A. Moultos
- Engineering
Thermodynamics, Process & Energy Department, Faculty of Mechanical,
Maritime and Materials Engineering, Delft
University of Technology, Leeghwaterstraat 39, 2628 CBDelft, The Netherlands
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23
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Willdorf-Cohen S, Kaushansky A, Dekel DR, Diesendruck CE. Hydroxide Chemoselectivity Changes with Water Microsolvation. J Phys Chem Lett 2022; 13:10216-10221. [PMID: 36288549 DOI: 10.1021/acs.jpclett.2c02637] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Solvent molecules are known to affect chemical reactions, especially if they interact with one or more of the reactants or catalysts. In ion microsolvation, i.e., solvent molecules in the first solvation sphere, strong electronic interactions are created, leading to significant changes in charge distribution and consequently on their nucleophilicity/electrophilicity and acidity/basicity. Despite a long history of research in the field, fundamental issues regarding the effects of ion microsolvation are still open, especially in the condensed phase. Using reactions between hydroxide and relatively stable quaternary ammonium salts as an example, we show that water microsolvation can change hydroxide's chemoselectivity by differently affecting its basicity and nucleophilicity. In this example, the hydroxide reactivity as a nucleophile is less affected by water microsolvation than its reactivity as a base. These disparities are discussed by calculating and comparing oxidation potentials and polarizabilities of the different water-hydroxide clusters.
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Affiliation(s)
- Sapir Willdorf-Cohen
- The Wolfson Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Alexander Kaushansky
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Dario R Dekel
- The Wolfson Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Charles E Diesendruck
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- The Nancy & Stephen Grand Technion Energy Program (GTEP), Technion-Israel Institute of Technology, Haifa 3200003, Israel
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24
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Zhu X, Iyengar SS. Graph Theoretic Molecular Fragmentation for Multidimensional Potential Energy Surfaces Yield an Adaptive and General Transfer Machine Learning Protocol. J Chem Theory Comput 2022; 18:5125-5144. [PMID: 35994592 DOI: 10.1021/acs.jctc.1c01241] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Over a series of publications we have introduced a graph-theoretic description for molecular fragmentation. Here, a system is divided into a set of nodes, or vertices, that are then connected through edges, faces, and higher-order simplexes to represent a collection of spatially overlapping and locally interacting subsystems. Each such subsystem is treated at two levels of electronic structure theory, and the result is used to construct many-body expansions that are then embedded within an ONIOM-scheme. These expansions converge rapidly with many-body order (or graphical rank) of subsystems and have been previously used for ab initio molecular dynamics (AIMD) calculations and for computing multidimensional potential energy surfaces. Specifically, in all these cases we have shown that CCSD and MP2 level AIMD trajectories and potential surfaces may be obtained at density functional theory cost. The approach has been demonstrated for gas-phase studies, for condensed phase electronic structure, and also for basis set extrapolation-based AIMD. Recently, this approach has also been used to derive new quantum-computing algorithms that enormously reduce the quantum circuit depth in a circuit-based computation of correlated electronic structure. In this publication, we introduce (a) a family of neural networks that act in parallel to represent, efficiently, the post-Hartree-Fock electronic structure energy contributions for all simplexes (fragments), and (b) a new k-means-based tessellation strategy to glean training data for high-dimensional molecular spaces and minimize the extent of training needed to construct this family of neural networks. The approach is particularly useful when coupled cluster accuracy is desired and when fragment sizes grow in order to capture nonlocal interactions accurately. The unique multidimensional k-means tessellation/clustering algorithm used to determine our training data for all fragments is shown to be extremely efficient and reduces the needed training to only 10% of data for all fragments to obtain accurate neural networks for each fragment. These fully connected dense neural networks are then used to extrapolate the potential energy surface for all molecular fragments, and these are then combined as per our graph-theoretic procedure to transfer the learning process to a full system energy for the entire AIMD trajectory at less than one-tenth the cost as compared to a regular fragmentation-based AIMD calculation.
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Affiliation(s)
- Xiao Zhu
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington 47405, Indiana, United States
| | - Srinivasan S Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington 47405, Indiana, United States
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25
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Joutsuka T. Molecular Mechanism of Autodissociation in Liquid Water: Ab Initio Molecular Dynamics Simulations. J Phys Chem B 2022; 126:4565-4571. [PMID: 35694850 DOI: 10.1021/acs.jpcb.2c01971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Autodissociation in liquid water is one of the most important processes in various topics of physical chemistry, such as acid-base chemistry. Molecular simulations have elucidated most of the molecular mechanisms at the atomic level, yet quantitative analysis to compare with experiments using the potential of mean force (PMF) remains a hurdle, including the definition of reaction coordinates and the accuracy of liquid structures by ab initio molecular dynamics (AIMD) simulations with density functional theory (DFT) methods. Here, we perform AIMD simulations with the revPBE-D3 exchange-correlation functional to compute the PMF profiles of autoionization, or proton transfer (PT), in liquid water. For the quantitative analysis with physically meaningful reaction coordinates, we employ a PT coordinate, donor-acceptor (OH--H3O+) distance, and hydrogen (H)-bond number. The one-dimensional (1D) PMF profile along the PT coordinate shows no local minimum in the product state of PT (OH- and H3O+), which is necessary to accurately compute the acid dissociation constant (or pKa). On the other hand, the 2D PMF profiles along the PT coordinate and donor-acceptor distance show local minima in the product state and reaction barriers, and the computed pKw is comparable to the experiment. In addition, the 2D PMF profiles along the PT coordinate and the H-bond number reveal the molecular mechanism of the H-bond rearrangement concomitant with PT, in which the H-bond breaking before PT is slightly preferable. These findings indicate that an accurate evaluation of pKa by MD simulations requires the donor-acceptor distance in addition to the conventional PT coordinate.
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Affiliation(s)
- Tatsuya Joutsuka
- Institute of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, Hitachi 316-8511 Ibaraki, Japan.,Frontier Research Center for Applied Atomic Sciences, Ibaraki University, 162-1 Shirakata, Tokai, 319-1106 Ibaraki, Japan
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26
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Mabuchi T. Revealing the Anticorrelation Behavior Mechanism between the Grotthuss and Vehicular Diffusions for Proton Transport in Concentrated Acid Solutions. J Phys Chem B 2022; 126:3319-3326. [PMID: 35468285 DOI: 10.1021/acs.jpcb.1c09742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we performed reactive molecular dynamics simulations to characterize proton solvation and transport in concentrated hydrochloric acid solutions. The correlation contribution to the total proton mean square displacement is found to be negative for all acid concentrations, indicating the anticorrelation between the Grotthuss and vehicular diffusions. For the vehicular diffusion, the hydronium ions tend to move freely toward the lone pair side independent of acid concentrations, whereas for the Grotthuss diffusion, the proton hopping direction is limited to one of the hydrogen-bonded water molecules on the opposite side of the lone pair region, which are specifically oriented with respect to the neighboring hydronium ion at higher acid concentrations. This result is justified by our findings of the higher fraction of proton rattling with the single hopping event and longer hydrogen bond lifetimes at higher acid concentrations. However, the angular distribution for both the vehicular and Grotthuss diffusions is found to be rather broad and comparable for all acid concentrations, and thus, the anticorrelation shows a minimal dependence on the acid concentration. Our results reveal that the anticorrelation behavior between the vehicle and Grotthuss diffusions is attributed to the amphiphilic nature of hydronium ions and thus is independent of the acid concentrations in solutions.
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Affiliation(s)
- Takuya Mabuchi
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan.,Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
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27
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Zelovich T, Tuckerman ME. Controlling Hydronium Diffusivity in Model Proton Exchange Membranes. J Phys Chem Lett 2022; 13:2245-2253. [PMID: 35238561 DOI: 10.1021/acs.jpclett.1c04071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Fuel-cell-based proton exchange membranes (PEMs) show great potential as cost-effective and clean energy conversion devices. In our recent work, we found that for the low-hydrated model PEMs with a inhomogeneous water distribution and a sulfonate anionic functional end group (SO3-), the H3O+ reacts with SO3- according to SO3- + H3O+ ↔ SO3H + H2O, indicating that the anions in PEMs become active participants in the hydronium diffusion. In this work, we use fully atomistic ab initio molecular dynamics simulations to elucidate the optimal conditions that would promote the participation of SO3- in the hydronium diffusion mechanism by increasing the H3O+/SO3- reactivity, thus increasing the hydronium diffusivity along the cell. The results presented in this work allow us to suggest a set of design rules for creating novel, highly conductive PEMs operating at high temperatures under a nonuniform water distribution using a linker/anion with a relatively high pKa such as (CH2)2SO3. We expect that the discovery of these key design principles will play an important role in the synthesis of high-performing materials for emerging PEM-based fuel cell technologies.
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Affiliation(s)
- Tamar Zelovich
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Mark E Tuckerman
- Department of Chemistry, New York University, New York, New York 10003, United States
- Courant Institute of Mathematical Sciences, New York University, New York, New York 10012, United States
- NYU-ECNU Center for Computational Chemistry, New York University Shanghai, 3663 North Zhongshan Rd, Shanghai 200062, China
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28
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Yang Y, Peltier CR, Zeng R, Schimmenti R, Li Q, Huang X, Yan Z, Potsi G, Selhorst R, Lu X, Xu W, Tader M, Soudackov AV, Zhang H, Krumov M, Murray E, Xu P, Hitt J, Xu L, Ko HY, Ernst BG, Bundschu C, Luo A, Markovich D, Hu M, He C, Wang H, Fang J, DiStasio RA, Kourkoutis LF, Singer A, Noonan KJT, Xiao L, Zhuang L, Pivovar BS, Zelenay P, Herrero E, Feliu JM, Suntivich J, Giannelis EP, Hammes-Schiffer S, Arias T, Mavrikakis M, Mallouk TE, Brock JD, Muller DA, DiSalvo FJ, Coates GW, Abruña HD. Electrocatalysis in Alkaline Media and Alkaline Membrane-Based Energy Technologies. Chem Rev 2022; 122:6117-6321. [PMID: 35133808 DOI: 10.1021/acs.chemrev.1c00331] [Citation(s) in RCA: 89] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hydrogen energy-based electrochemical energy conversion technologies offer the promise of enabling a transition of the global energy landscape from fossil fuels to renewable energy. Here, we present a comprehensive review of the fundamentals of electrocatalysis in alkaline media and applications in alkaline-based energy technologies, particularly alkaline fuel cells and water electrolyzers. Anion exchange (alkaline) membrane fuel cells (AEMFCs) enable the use of nonprecious electrocatalysts for the sluggish oxygen reduction reaction (ORR), relative to proton exchange membrane fuel cells (PEMFCs), which require Pt-based electrocatalysts. However, the hydrogen oxidation reaction (HOR) kinetics is significantly slower in alkaline media than in acidic media. Understanding these phenomena requires applying theoretical and experimental methods to unravel molecular-level thermodynamics and kinetics of hydrogen and oxygen electrocatalysis and, particularly, the proton-coupled electron transfer (PCET) process that takes place in a proton-deficient alkaline media. Extensive electrochemical and spectroscopic studies, on single-crystal Pt and metal oxides, have contributed to the development of activity descriptors, as well as the identification of the nature of active sites, and the rate-determining steps of the HOR and ORR. Among these, the structure and reactivity of interfacial water serve as key potential and pH-dependent kinetic factors that are helping elucidate the origins of the HOR and ORR activity differences in acids and bases. Additionally, deliberately modulating and controlling catalyst-support interactions have provided valuable insights for enhancing catalyst accessibility and durability during operation. The design and synthesis of highly conductive and durable alkaline membranes/ionomers have enabled AEMFCs to reach initial performance metrics equal to or higher than those of PEMFCs. We emphasize the importance of using membrane electrode assemblies (MEAs) to integrate the often separately pursued/optimized electrocatalyst/support and membranes/ionomer components. Operando/in situ methods, at multiscales, and ab initio simulations provide a mechanistic understanding of electron, ion, and mass transport at catalyst/ionomer/membrane interfaces and the necessary guidance to achieve fuel cell operation in air over thousands of hours. We hope that this Review will serve as a roadmap for advancing the scientific understanding of the fundamental factors governing electrochemical energy conversion in alkaline media with the ultimate goal of achieving ultralow Pt or precious-metal-free high-performance and durable alkaline fuel cells and related technologies.
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Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Cheyenne R Peltier
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Rui Zeng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Roberto Schimmenti
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Qihao Li
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Xin Huang
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Zhifei Yan
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Georgia Potsi
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Ryan Selhorst
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Xinyao Lu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Weixuan Xu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Mariel Tader
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Alexander V Soudackov
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Hanguang Zhang
- Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Mihail Krumov
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Ellen Murray
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Pengtao Xu
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Jeremy Hitt
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Linxi Xu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Hsin-Yu Ko
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Brian G Ernst
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Colin Bundschu
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Aileen Luo
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Danielle Markovich
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Meixue Hu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Cheng He
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Hongsen Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Jiye Fang
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, United States
| | - Robert A DiStasio
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Lena F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Andrej Singer
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Kevin J T Noonan
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Li Xiao
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Lin Zhuang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Bryan S Pivovar
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Piotr Zelenay
- Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Enrique Herrero
- Instituto de Electroquímica, Universidad de Alicante, Alicante E-03080, Spain
| | - Juan M Feliu
- Instituto de Electroquímica, Universidad de Alicante, Alicante E-03080, Spain
| | - Jin Suntivich
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Emmanuel P Giannelis
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | | | - Tomás Arias
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Manos Mavrikakis
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Thomas E Mallouk
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Joel D Brock
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - David A Muller
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Geoffrey W Coates
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.,Center for Alkaline Based Energy Solutions (CABES), Cornell University, Ithaca, New York 14853, United States
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29
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Vazquez de Vasquez MG, Carter-Fenk KA, McCaslin LM, Beasley EE, Clark JB, Allen HC. Hydration and Hydrogen Bond Order of Octadecanoic Acid and Octadecanol Films on Water at 21 and 1 °C. J Phys Chem A 2021; 125:10065-10078. [PMID: 34761931 DOI: 10.1021/acs.jpca.1c06101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The temperature-dependent hydration structure of long-chain fatty acids and alcohols at air-water interfaces has great significance in the fundamental interactions underlying ice nucleation in the atmosphere. We present an integrated theoretical and experimental study of the temperature-dependent vibrational structure and electric field character of the immediate hydration shells of fatty alcohol and acid headgroups. We use a combination of surface-sensitive infrared reflection-absorption spectroscopy (IRRAS), surface potentiometry, and ab initio molecular dynamics simulations to elucidate detailed molecular structures of the octadecanoic acid and octadecanol (stearic acid and stearyl alcohol) headgroup hydration shells at room temperature and near freezing. In experiments, the alcohol at high surface concentration exhibits the largest surface potential; yet we observe a strengthening of the hydrogen-bonding for the solvating water molecules near freezing for both the alcohol and the fatty acid IRRAS experiments. Results reveal that the hydration shells for both compounds screen their polar headgroup dipole moments reducing the surface potential at low surface coverages; at higher surface coverage, the polar headgroups become dehydrated, which reduces the screening, correlating to higher observed surface potential values. Lowering the temperature promotes tighter chain packing and an increase in surface potential. IRRAS reveals that the intra- and intermolecular vibrational coupling mechanisms are highly sensitive to changes in temperature. We find that intramolecular coupling dominates the vibrational relaxation pathways for interfacial water determined by comparing the H2O and the HOD spectra. Using ab initio molecular dynamics (AIMD) calculations on cluster systems of propanol + 6H2O and propionic acid + 10H2O, a spectral decomposition scheme was used to correlate the OH stretching motion with the IRRAS spectral features, revealing the effects of intra- and intermolecular coupling on the spectra. Spectra calculated with AIMD reproduce the red shift and increase in intensity observed in experimental spectra corresponding to the OH stretching region of the first solvation shell. These findings suggest that intra- and intermolecular vibrational couplings strongly impact the OH stretching region at fatty acid and fatty alcohol water interfaces. Overall, results are consistent with ice templating behavior for both the fatty acid and the alcohol, yet the surface potential signature is strongest for the fatty alcohol. These findings develop a better understanding of the complex surface potential and spectral signatures involved in ice templating.
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Affiliation(s)
- Maria G Vazquez de Vasquez
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Kimberly A Carter-Fenk
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Laura M McCaslin
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, United States
| | - Emma E Beasley
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Jessica B Clark
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Heather C Allen
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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30
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Adams EM, Hao H, Leven I, Rüttermann M, Wirtz H, Havenith M, Head‐Gordon T. Proton Traffic Jam: Effect of Nanoconfinement and Acid Concentration on Proton Hopping Mechanism. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ellen M. Adams
- Lehrstuhl für Physkalische Chemie II Ruhr Universität Bochum 44801 Bochum Germany
| | - Hongxia Hao
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA
- Kenneth S. Pitzer Center for Theoretical Chemistry University of California Berkeley California 94720 USA
- Department of Chemistry University of California Berkeley California 94720 USA
| | - Itai Leven
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA
- Kenneth S. Pitzer Center for Theoretical Chemistry University of California Berkeley California 94720 USA
- Department of Chemistry University of California Berkeley California 94720 USA
| | | | - Hanna Wirtz
- Lehrstuhl für Physkalische Chemie II Ruhr Universität Bochum 44801 Bochum Germany
| | - Martina Havenith
- Lehrstuhl für Physkalische Chemie II Ruhr Universität Bochum 44801 Bochum Germany
| | - Teresa Head‐Gordon
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA
- Kenneth S. Pitzer Center for Theoretical Chemistry University of California Berkeley California 94720 USA
- Department of Chemistry University of California Berkeley California 94720 USA
- Department of Chemical and Biomolecular Engineering University of California Berkeley California 94720 USA
- Department of Bioengineering University of California Berkeley California 94720 USA
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31
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Ohmine I, Saito S. Dynamical Behavior of Water; Fluctuation, Reactions and Phase Transitions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Iwao Ohmine
- Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Shinji Saito
- Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan
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32
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Corti HR, Appignanesi GA, Barbosa MC, Bordin JR, Calero C, Camisasca G, Elola MD, Franzese G, Gallo P, Hassanali A, Huang K, Laria D, Menéndez CA, de Oca JMM, Longinotti MP, Rodriguez J, Rovere M, Scherlis D, Szleifer I. Structure and dynamics of nanoconfined water and aqueous solutions. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2021; 44:136. [PMID: 34779954 DOI: 10.1140/epje/s10189-021-00136-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
This review is devoted to discussing recent progress on the structure, thermodynamic, reactivity, and dynamics of water and aqueous systems confined within different types of nanopores, synthetic and biological. Currently, this is a branch of water science that has attracted enormous attention of researchers from different fields interested to extend the understanding of the anomalous properties of bulk water to the nanoscopic domain. From a fundamental perspective, the interactions of water and solutes with a confining surface dramatically modify the liquid's structure and, consequently, both its thermodynamical and dynamical behaviors, breaking the validity of the classical thermodynamic and phenomenological description of the transport properties of aqueous systems. Additionally, man-made nanopores and porous materials have emerged as promising solutions to challenging problems such as water purification, biosensing, nanofluidic logic and gating, and energy storage and conversion, while aquaporin, ion channels, and nuclear pore complex nanopores regulate many biological functions such as the conduction of water, the generation of action potentials, and the storage of genetic material. In this work, the more recent experimental and molecular simulations advances in this exciting and rapidly evolving field will be reported and critically discussed.
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Affiliation(s)
- Horacio R Corti
- Departmento de Física de la Materia Condensada & Instituto de Nanociencia y Nanotecnología (CNEA-CONICET), Comisión Nacional de Energía Atómica, B1650LWP, Buenos Aires, Argentina.
| | - Gustavo A Appignanesi
- INQUISUR, Departamento de Química, Universidad Nacional del Sur (UNS)-CONICET, 8000, Bahía Blanca, Argentina
| | - Marcia C Barbosa
- Institute of Physics, Federal University of Rio Grande do Sul, 91501-970, Porto Alegre, Brazil
| | - J Rafael Bordin
- Department of Physics, Institute of Physics and Mathematics, 96050-500, Pelotas, RS, Brazil
| | - Carles Calero
- Secció de Física Estadística i Interdisciplinària - Departament de Física de la Matèria Condensada, Universitat de Barcelona & Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, 08028, Barcelona, Spain
| | - Gaia Camisasca
- Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre, 00146, Roma, Italy
| | - M Dolores Elola
- Departmento de Física de la Materia Condensada & Instituto de Nanociencia y Nanotecnología (CNEA-CONICET), Comisión Nacional de Energía Atómica, B1650LWP, Buenos Aires, Argentina
| | - Giancarlo Franzese
- Secció de Física Estadística i Interdisciplinària - Departament de Física de la Matèria Condensada, Universitat de Barcelona & Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, 08028, Barcelona, Spain
| | - Paola Gallo
- Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre, 00146, Roma, Italy
| | - Ali Hassanali
- Condensed Matter and Statistical Physics Section (CMSP), The International Center for Theoretical Physics (ICTP), Trieste, Italy
| | - Kai Huang
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, Guangdong, China
| | - Daniel Laria
- Departmento de Física de la Materia Condensada & Instituto de Nanociencia y Nanotecnología (CNEA-CONICET), Comisión Nacional de Energía Atómica, B1650LWP, Buenos Aires, Argentina
- Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE-CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Cintia A Menéndez
- INQUISUR, Departamento de Química, Universidad Nacional del Sur (UNS)-CONICET, 8000, Bahía Blanca, Argentina
| | - Joan M Montes de Oca
- INQUISUR, Departamento de Química, Universidad Nacional del Sur (UNS)-CONICET, 8000, Bahía Blanca, Argentina
| | - M Paula Longinotti
- Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE-CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Javier Rodriguez
- Departmento de Física de la Materia Condensada & Instituto de Nanociencia y Nanotecnología (CNEA-CONICET), Comisión Nacional de Energía Atómica, B1650LWP, Buenos Aires, Argentina
- Escuela de Ciencia y Tecnología, Universidad Nacional de General San Martín, San Martín, Buenos Aires, Argentina
| | - Mauro Rovere
- Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre, 00146, Roma, Italy
| | - Damián Scherlis
- Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE-CONICET), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Igal Szleifer
- Biomedical Engineering Department, Northwestern University, Evanston, USA
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33
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Calio PB, Li C, Voth GA. Resolving the Structural Debate for the Hydrated Excess Proton in Water. J Am Chem Soc 2021; 143:18672-18683. [PMID: 34723507 DOI: 10.1021/jacs.1c08552] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
It has long been proposed that the hydrated excess proton in water (aka the solvated "hydronium" cation) likely has two limiting forms, that of the Eigen cation (H9O4+) and that of the Zundel cation (H5O2+). There has been debate over which of these two is the more dominant species and/or whether intermediate (or "distorted") structures between these two limits are the more realistic representation. Spectroscopy experiments have recently provided further results regarding the excess proton. These experiments show that the hydrated proton has an anisotropy reorientation time scale on the order of 1-2 ps. This time scale has been suggested to possibly contradict the picture of the more rapid "special pair dance" phenomenon for the hydrated excess proton, which is a signature of a distorted Eigen cation. The special pair dance was predicted from prior computational studies in which the hydrated central core hydronium structure continually switches (O-H···O)* special pair hydrogen-bond partners with the closest three water molecules, yielding on average a distorted Eigen cation with three equivalent and dynamically exchanging distortions. Through state-of-art simulations it is shown here that anisotropy reorientation time scales of the same magnitude are obtained that also include structural reorientations associated with the special pair dance, leading to a reinterpretation of the experimental results. These results and additional analyses point to a distorted and dynamic Eigen cation as the most prevalent hydrated proton species in aqueous acid solutions of dilute to moderate concentration, as opposed to a stabilized or a distorted (but not "dancing") Zundel cation.
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Affiliation(s)
- Paul B Calio
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Chenghan Li
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
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34
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Kumar A, DeGregorio N, Iyengar SS. Graph-Theory-Based Molecular Fragmentation for Efficient and Accurate Potential Surface Calculations in Multiple Dimensions. J Chem Theory Comput 2021; 17:6671-6690. [PMID: 34623129 DOI: 10.1021/acs.jctc.1c00065] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We present a multitopology molecular fragmentation approach, based on graph theory, to calculate multidimensional potential energy surfaces in agreement with post-Hartree-Fock levels of theory but at the density functional theory cost. A molecular assembly is coarse-grained into a set of graph-theoretic nodes that are then connected with edges to represent a collection of locally interacting subsystems up to an arbitrary order. Each of the subsystems is treated at two levels of electronic structure theory, the result being used to construct many-body expansions that are embedded within an ONIOM scheme. These expansions converge rapidly with the many-body order (or graphical rank) of subsystems and capture many-body interactions accurately and efficiently. However, multiple graphs, and hence multiple fragmentation topologies, may be defined in molecular configuration space that may arise during conformational sampling or from reactive, bond breaking and bond formation, events. Obtaining the resultant potential surfaces is an exponential scaling proposition, given the number of electronic structure computations needed. We utilize a family of graph-theoretic representations within a variational scheme to obtain multidimensional potential surfaces at a reduced cost. The fast convergence of the graph-theoretic expansion with increasing order of many-body interactions alleviates the exponential scaling cost for computing potential surfaces, with the need to only use molecular fragments that contain a fewer number of quantum nuclear degrees of freedom compared to the full system. This is because the dimensionality of the conformational space sampled by the fragment subsystems is much smaller than the full molecular configurational space. Additionally, we also introduce a multidimensional clustering algorithm, based on physically defined criteria, to reduce the number of energy calculations by orders of magnitude. The molecular systems benchmarked include coupled proton motion in protonated water wires. The potential energy surfaces and multidimensional nuclear eigenstates obtained are shown to be in very good agreement with those from explicit post-Hartree-Fock calculations that become prohibitive as the number of quantum nuclear dimensions grows. The developments here provide a rigorous and efficient alternative to this important chemical physics problem.
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Affiliation(s)
- Anup Kumar
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Nicole DeGregorio
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Srinivasan S Iyengar
- Department of Chemistry and Department of Physics, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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35
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Kronberg R, Laasonen K. Dynamics and Surface Propensity of H + and OH - within Rigid Interfacial Water: Implications for Electrocatalysis. J Phys Chem Lett 2021; 12:10128-10134. [PMID: 34636561 PMCID: PMC8543677 DOI: 10.1021/acs.jpclett.1c02493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/29/2021] [Indexed: 06/13/2023]
Abstract
Facile solvent reorganization promoting ion transfer across the solid-liquid interface is considered a prerequisite for efficient electrocatalysis. We provide first-principles insight into this notion by examining water self-ion dynamics at a highly rigid NaCl(100)-water interface. Through extensive density functional theory molecular dynamics simulations, we demonstrate for both acidic and alkaline solutions that Grotthuss dynamics is not impeded by a rigid water structure. Conversely, decreased proton transfer barriers and a striking propensity of H3O+ and OH- for stationary interfacial water are found. Differences in the ideal hydration structure of the ions, however, distinguish their behavior at the water contact layer. While hydronium can maintain its optimal solvation, the preferentially hypercoordinated hydroxide is repelled from the immediate vicinity of the surface due to interfacial coordination reduction. This has implications for alkaline hydrogen electrosorption in which the formation of undercoordinated OH- at the surface is proposed to contribute to the observed sluggish kinetics.
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36
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Atsango AO, Tuckerman ME, Markland TE. Characterizing and Contrasting Structural Proton Transport Mechanisms in Azole Hydrogen Bond Networks Using Ab Initio Molecular Dynamics. J Phys Chem Lett 2021; 12:8749-8756. [PMID: 34478302 DOI: 10.1021/acs.jpclett.1c02266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Imidazole and 1,2,3-triazole are promising hydrogen-bonded heterocycles that conduct protons via a structural mechanism and whose derivatives are present in systems ranging from biological proton channels to proton exchange membrane fuel cells. Here, we leverage multiple time-stepping to perform ab initio molecular dynamics of imidazole and 1,2,3-triazole at the nanosecond time scale. We show that despite the close structural similarities of these compounds, their proton diffusion constants vary by over an order of magnitude. Our simulations reveal the reasons for these differences in diffusion constants, which range from the degree of hydrogen-bonded chain linearity to the effect of the central nitrogen atom in 1,2,3-triazole on proton transport. In particular, we uncover evidence of two "blocking" mechanisms in 1,2,3-triazole, where covalent and hydrogen bonds formed by the central nitrogen atom limit the mobility of protons. Our simulations thus provide insights into the origins of the experimentally observed 10-fold difference in proton conductivity.
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Affiliation(s)
- Austin O Atsango
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mark E Tuckerman
- Department of Chemistry, New York University, New York, New York 10003, United States
- Courant Institute of Mathematical Science, New York University, New York, New York 10012, United States
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China
| | - Thomas E Markland
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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37
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Havenith-Newen M, Adams EM, Head-Gordon T, Hao H, Rüttermann M, Leven I, Wirtz H. Proton Traffic Jam: Effect of Nanoconfinement and Acid Concentration on Proton Hopping Mechanism. Angew Chem Int Ed Engl 2021; 60:25419-25427. [PMID: 34402145 PMCID: PMC9293324 DOI: 10.1002/anie.202108766] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Indexed: 11/06/2022]
Abstract
The properties of the water network in concentrated HCl acid pools in nanometer-sized reverse non-ionic micelles were probed with TeraHertz absorption, dielectric relaxation spectroscopy, and reactive force field simulations capable of describing proton hopping mechanisms. We identify that only at a critical micelle size of W0=9 do solvated proton complexes form in the water pool, accompanied by a change in mechanism from Grotthuss forward shuttling to one that favors local oscillatory hopping. This is due to a preference for H+ and Cl- ions to adsorb to the micelle interface, together with an acid concentration effect that causes a "traffic jam" in which the short-circuiting of the hydrogen-bonding motif of the hydronium ion decreases the forward hopping rate throughout the water interior even as the micelle size increases. These findings have implications for atmospheric chemistry, biochemical and biophysical environments, and energy materials, as transport of protons vital to these processes can be suppressed due to confinement, aggregation, and/or concentration.
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Affiliation(s)
- Martina Havenith-Newen
- Ruhr-Universit�t Bochum, Physical Chemistry, Universit�tsstr. 150, 44780, Bochum, GERMANY
| | - Ellen M Adams
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum, Chemistry and Biochemistry, GERMANY
| | - Teresa Head-Gordon
- UC Berkeley: University of California Berkeley, Chemistry, UNITED STATES
| | - Hongxia Hao
- Berkeley Laboratory: E O Lawrence Berkeley National Laboratory, Chemistry, UNITED STATES
| | | | - Itai Leven
- Lawrence Livermore National Laboratory, chemistry, GERMANY
| | - Hanna Wirtz
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum, Chemistry, GERMANY
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38
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Arntsen C, Chen C, Calio PB, Li C, Voth GA. The hopping mechanism of the hydrated excess proton and its contribution to proton diffusion in water. J Chem Phys 2021; 154:194506. [PMID: 34240917 DOI: 10.1063/5.0040758] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In this work, a series of analyses are performed on ab initio molecular dynamics simulations of a hydrated excess proton in water to quantify the relative occurrence of concerted hopping events and "rattling" events and thus to further elucidate the hopping mechanism of proton transport in water. Contrary to results reported in certain earlier papers, the new analysis finds that concerted hopping events do occur in all simulations but that the majority of events are the product of proton rattling, where the excess proton will rattle between two or more waters. The results are consistent with the proposed "special-pair dance" model of the hydrated excess proton wherein the acceptor water molecule for the proton transfer will quickly change (resonate between three equivalent special pairs) until a decisive proton hop occurs. To remove the misleading effect of simple rattling, a filter was applied to the trajectory such that hopping events that were followed by back hops to the original water are not counted. A steep reduction in the number of multiple hopping events is found when the filter is applied, suggesting that many multiple hopping events that occur in the unfiltered trajectory are largely the product of rattling, contrary to prior suggestions. Comparing the continuous correlation function of the filtered and unfiltered trajectories, we find agreement with experimental values for the proton hopping time and Eigen-Zundel interconversion time, respectively.
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Affiliation(s)
- Christopher Arntsen
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA
| | - Chen Chen
- Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Paul B Calio
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Chenghan Li
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
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39
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Zelovich T, Tuckerman ME. OH - and H 3O + Diffusion in Model AEMs and PEMs at Low Hydration: Insights from Ab Initio Molecular Dynamics. MEMBRANES 2021; 11:355. [PMID: 34066142 PMCID: PMC8151131 DOI: 10.3390/membranes11050355] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/25/2021] [Accepted: 05/06/2021] [Indexed: 11/27/2022]
Abstract
Fuel cell-based anion-exchange membranes (AEMs) and proton exchange membranes (PEMs) are considered to have great potential as cost-effective, clean energy conversion devices. However, a fundamental atomistic understanding of the hydroxide and hydronium diffusion mechanisms in the AEM and PEM environment is an ongoing challenge. In this work, we aim to identify the fundamental atomistic steps governing hydroxide and hydronium transport phenomena. The motivation of this work lies in the fact that elucidating the key design differences between the hydroxide and hydronium diffusion mechanisms will play an important role in the discovery and determination of key design principles for the synthesis of new membrane materials with high ion conductivity for use in emerging fuel cell technologies. To this end, ab initio molecular dynamics simulations are presented to explore hydroxide and hydronium ion solvation complexes and diffusion mechanisms in the model AEM and PEM systems at low hydration in confined environments. We find that hydroxide diffusion in AEMs is mostly vehicular, while hydronium diffusion in model PEMs is structural. Furthermore, we find that the region between each pair of cations in AEMs creates a bottleneck for hydroxide diffusion, leading to a suppression of diffusivity, while the anions in PEMs become active participants in the hydronium diffusion, suggesting that the presence of the anions in model PEMs could potentially promote hydronium diffusion.
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Affiliation(s)
- Tamar Zelovich
- Department of Chemistry, New York University (NYU), New York 10003, NY, USA
| | - Mark E. Tuckerman
- Department of Chemistry, New York University (NYU), New York 10003, NY, USA
- Courant Institute of Mathematical Sciences, New York University (NYU), New York, NY 10012, USA
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Rd. North, Shanghai 200062, China
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40
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Zeng HJ, Johnson MA. Demystifying the Diffuse Vibrational Spectrum of Aqueous Protons Through Cold Cluster Spectroscopy. Annu Rev Phys Chem 2021; 72:667-691. [PMID: 33646816 DOI: 10.1146/annurev-physchem-061020-053456] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ease with which the pH is routinely determined for aqueous solutions masks the fact that the cationic product of Arrhenius acid dissolution, the hydrated proton, or H+(aq), is a remarkably complex species. Here, we review how results obtained over the past 30 years in the study of H+⋅(H2O)n cluster ions isolated in the gas phase shed light on the chemical nature of H+(aq). This effort has also revealed molecular-level aspects of the Grotthuss relay mechanism for positive-charge translocation in water. Recently developed methods involving cryogenic cooling in radiofrequency ion traps and the application of two-color, infrared-infrared (IR-IR) double-resonance spectroscopy have established a clear picture of how local hydrogen-bond topology drives the diverse spectral signatures of the excess proton. This information now enables a new generation of cluster studies designed to unravel the microscopic mechanics underlying the ultrafast relaxation dynamics displayed by H+(aq).
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Affiliation(s)
- Helen J Zeng
- Sterling Chemistry Laboratory, Yale University, New Haven, Connecticut 06520, USA;
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Yale University, New Haven, Connecticut 06520, USA;
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41
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Watanabe HC, Yamada M, Suzuki Y. Proton transfer in bulk water using the full adaptive QM/MM method: integration of solute- and solvent-adaptive approaches. Phys Chem Chem Phys 2021; 23:8344-8360. [PMID: 33875999 DOI: 10.1039/d1cp00116g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The quantum mechanical/molecular mechanical (QM/MM) method is a hybrid molecular simulation technique that increases the accessibility of local electronic structures of large systems. The technique combines the benefit of accuracy found in the QM method and that of cost efficiency found in the MM method. However, it is difficult to directly apply the QM/MM method to the dynamics of solution systems, particularly for proton transfer. As explained in the Grotthuss mechanism, proton transfer is a structural interconversion between hydronium ions and solvent water molecules. Hence, when the QM/MM method is applied, an adaptive treatment, namely on-the-fly revisions on molecular definitions, is required for both the solute and solvent. Although several solvent-adaptive methods have been proposed, a full adaptive framework, which is an approach that also considers adaptation for solutes, remains untapped. In this paper, we propose a new numerical expression for the coordinates of the excess proton and its control algorithm. Furthermore, we confirm that this method can stably and accurately simulate proton transfer dynamics in bulk water.
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Affiliation(s)
- Hiroshi C Watanabe
- Quantum Computing Center, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
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42
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Clark AD, Lee WL, Solano AR, Williams TB, Meyer GS, Tait GJ, Battraw BC, Nickerson SD. Complexation of Mo in FLiNaK Molten Salt: Insight from Ab Initio Molecular Dynamics. J Phys Chem B 2021; 125:211-218. [PMID: 33373244 DOI: 10.1021/acs.jpcb.0c07354] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Online extraction of fission products, such as the medical isotope Mo-99, is a key advantage of the proposed molten salt nuclear reactor design. The chemical and structural behavior of Mo solvated in fluoride salt has been relatively unknown. Ab initio molecular dynamics simulations were employed to examine the behavior of molybdenum in the molten salt FLiNaK (LiF-NaF-KF) for oxidation states between 0 and 6+. Mo complexation was found to vary with the Mo oxidation state, with lower oxidation states tending to result in complexes with more molybdenum ions. Complexes containing multiple Mo ions were observed for all Mo oxidation states studied except 5+ and 6+. A relationship between the solubility of a complex and electronic isolation of a complex in a molten salt is explored using the Bader atoms in molecule electron density partitioning scheme, with more volatile complexes exhibiting greater electronic isolation. The impacts of UF4 and H2O on the predominant molybdenum species are also considered. While no impacts on Mo behavior by UF4 were observed, Mo-O interactions may inhibit the formation of complexes containing multiple Mo ions.
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Affiliation(s)
- Austin David Clark
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Wan Luan Lee
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Andrew Russell Solano
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Tyler Bruce Williams
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Gabriel Scott Meyer
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Granite J Tait
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Ben C Battraw
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
| | - Stella D Nickerson
- Department of Chemical Engineering, Brigham Young University, Provo, Utah 84602, United States
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43
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Wei Y, Chin K, Barge LM, Perl S, Hermis N, Wei T. Machine Learning Analysis of the Thermodynamic Responses of In Situ Dielectric Spectroscopy Data in Amino Acids and Inorganic Electrolytes. J Phys Chem B 2020; 124:11491-11500. [PMID: 33284009 DOI: 10.1021/acs.jpcb.0c09266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dielectric spectroscopy (DS) can be a robust in situ technique for geochemical applications. In this study, we applied deep-learning techniques to DS measurement data to enable rapid science interrogation and identification of electrolyte solutions containing salts and amino acids over a wide temperature range (20 to -60 °C). For the purpose of searching for signs of life, detecting amino acids is a fundamental high priority for field and planetary instruments as amino acids are one of the building blocks for life as we know it. A convolutional neural network (CNN) with channel-wise one-dimensional filters is proposed to fulfill the task, using the DS data of amino acid and inorganic salt solutions. Experimental results show that the CNN with two convolutional layers and one fully connected layer can effectively differentiate solutions containing amino acids from those containing salts in both the liquid and solid (water ice) states. To complement the experimental measurements and CNN analysis, the diffusive behaviors of ions (K+, Cl-, and OH-) were further discussed with atomistic molecular dynamics simulations performed in this work as well as the quantum simulation published in the literature. Combining DS with machine-learning techniques and simulations will greatly facilitate more real-time decision-making of mobility systems for future exploratory endeavors in other worlds beyond Earth.
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Affiliation(s)
- Yong Wei
- Department of Computer Science and Information Systems, University of North Georgia, Dahlonega, Georgia 30597, United States
| | - Keith Chin
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Laura M Barge
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Scott Perl
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Ninos Hermis
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Tao Wei
- Chemical Engineering Department, Howard University, Washington, D.C. 20059, United States
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44
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Lu L, Wildman A, Jenkins AJ, Young L, Clark AE, Li X. The "Hole" Story in Ionized Water from the Perspective of Ehrenfest Dynamics. J Phys Chem Lett 2020; 11:9946-9951. [PMID: 33170721 DOI: 10.1021/acs.jpclett.0c02987] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The radiolysis of liquid water and the radiation-matter interactions that happen in aqueous environments are important to the fields of chemistry, materials, and environmental sciences, as well as the biological and physiological response to extreme conditions and medical treatments. The initial stage of radiolysis is the ultrafast response, or hole dynamics, that triggers chemical processes within complex energetic landscapes that may include reactivity. A fundamental understanding necessitates the use of theoretical methods that are capable of simulating both ultrafast coherence and non-adiabatic energy transfer pathways. In this work, we carry out an ab initio Ehrenfest dynamics study to provide a more complete description of the ultrafast dynamics and reactive events initiated by photoionization of water. After sudden ionization, a range of processes, including hole trapping and transfer, large OH oscillations, proton transfer and subsequent relay, formation of the metastable Zundel complex, and long-lived coherence, are identified and new insight into their driving forces is elucidated.
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Affiliation(s)
- Lixin Lu
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Andrew Wildman
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Andrew J Jenkins
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Linda Young
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Department of Physics and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - Aurora E Clark
- Department of Chemistry, Washington State University, Pullman, Washington 99164, United States
- Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
- Pacific Northwest National Laboratory, Richland, Washington 99354, United States
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45
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Borah S, Kumar PP. Hydration structure of As–III aqueous solutions from ab initio molecular dynamics simulations. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.114056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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46
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Calio PB, Li C, Voth GA. Molecular Origins of the Barriers to Proton Transport in Acidic Aqueous Solutions. J Phys Chem B 2020; 124:8868-8876. [PMID: 32924490 DOI: 10.1021/acs.jpcb.0c06223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The self-consistent iterative multistate empirical valence bond (SCI-MS-EVB) method is used to analyze the structure, thermodynamics, and dynamics of hydrochloric acid solutions. The reorientation time scales of irreversible proton transport are elucidated by simulating 0.43, 0.85, 1.68, and 3.26 M HCl solutions at 270, 285, 300, 315, and 330 K. The results indicate increased counterion pairing with increasing concentration, which manifests itself via a reduced hydronium oxygen-chloride (O*-Cl) structuring in the radial distribution functions. Increasing ionic concentration also reduces the diffusion of the hydrated excess protons, principally by reducing the contribution of the Grotthuss proton hopping (shuttling) mechanism to the overall diffusion process. In agreement with prior experimental findings, a decrease in the activation energy of reorientation time scales was also observed, which is explicitly explained by using activated rate theory and an energy-entropy decomposition of the state-averaged radial distribution functions. These results provide atomistic verification of suggestions from recent two-dimensional infrared spectroscopy experiments that chloride anions (as opposed to hydrated excess protons) create entropic barriers to proton transport.
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Affiliation(s)
- Paul B Calio
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Chenghan Li
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
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47
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Carpenter WB, Yu Q, Hack JH, Dereka B, Bowman JM, Tokmakoff A. Decoding the 2D IR spectrum of the aqueous proton with high-level VSCF/VCI calculations. J Chem Phys 2020; 153:124506. [PMID: 33003749 DOI: 10.1063/5.0020279] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The aqueous proton is a common and long-studied species in chemistry, yet there is currently intense interest devoted to understanding its hydration structure and transport dynamics. Typically described in terms of two limiting structures observed in gas-phase clusters, the Zundel H5O2 + and Eigen H9O4 + ions, the aqueous structure is less clear due to the heterogeneity of hydrogen bonding environments and room-temperature structural fluctuations in water. The linear infrared (IR) spectrum, which reports on structural configurations, is challenging to interpret because it appears as a continuum of absorption, and the underlying vibrational modes are strongly anharmonically coupled to each other. Recent two-dimensional IR (2D IR) experiments presented strong evidence for asymmetric Zundel-like motifs in solution, but true structure-spectrum correlations are missing and complicated by the anharmonicity of the system. In this study, we employ high-level vibrational self-consistent field/virtual state configuration interaction calculations to demonstrate that the 2D IR spectrum reports on a broad distribution of geometric configurations of the aqueous proton. We find that the diagonal 2D IR spectrum around 1200 cm-1 is dominated by the proton stretch vibrations of Zundel-like and intermediate geometries, broadened by the heterogeneity of aqueous configurations. There is a wide distribution of multidimensional potential shapes for the proton stretching vibration with varying degrees of potential asymmetry and confinement. Finally, we find specific cross peak patterns due to aqueous Zundel-like species. These studies provide clarity on highly debated spectral assignments and stringent spectroscopic benchmarks for future simulations.
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Affiliation(s)
- William B Carpenter
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Qi Yu
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - John H Hack
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Bogdan Dereka
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
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48
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Long Z, Atsango AO, Napoli JA, Markland TE, Tuckerman ME. Elucidating the Proton Transport Pathways in Liquid Imidazole with First-Principles Molecular Dynamics. J Phys Chem Lett 2020; 11:6156-6163. [PMID: 32633523 DOI: 10.1021/acs.jpclett.0c01744] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Imidazole is a promising anhydrous proton conductor with a high conductivity comparable to that of water at a similar temperature relative to its melting point. Previous theoretical studies of the mechanism of proton transport in imidazole have relied either on empirical models or on ab initio trajectories that have been too short to draw significant conclusions. Here, we present the results of multiple time-step ab initio molecular dynamics simulations of an excess proton in liquid imidazole reaching 1 ns in total simulation time. We find that the proton transport is dominated by structural diffusion, with the diffusion constant of the proton defect being ∼8 times higher than that of self-diffusion of the imidazole molecules. By using correlation function analysis, we decompose the mechanism for proton transport into a series of first-order processes and show that the proton transport mechanism occurs over three distinct time and length scales. Although the mechanism at intermediate times is dominated by hopping along pseudo-one-dimensional chains, at longer times the overall rate of diffusion is limited by the re-formation of these chains. These results provide a more complete picture of the traditional idealized Grotthuss structural diffusion mechanism.
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Affiliation(s)
- Zhuoran Long
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Austin O Atsango
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Joseph A Napoli
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Thomas E Markland
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mark E Tuckerman
- Department of Chemistry, New York University, New York, New York 10003, United States
- Courant Institute of Mathematical Science, New York University, New York, New York 10012, United States
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China
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Borah S. Spatially resolved hydration shells and dynamics of different sulfur species in water from first-principle molecular dynamics simulations. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Calio PB, Hocky GM, Voth GA. Minimal Experimental Bias on the Hydrogen Bond Greatly Improves Ab Initio Molecular Dynamics Simulations of Water. J Chem Theory Comput 2020; 16:5675-5684. [DOI: 10.1021/acs.jctc.0c00558] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paul B. Calio
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Glen M. Hocky
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Gregory A. Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
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