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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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2
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Wan Iskandar WFN, Salim M, Patrick M, Timimi BA, Zahid NI, Hashim R. Probing n-Octyl α-d-Glycosides Using Deuterated Water in the Lyotropic Phase by Deuterium NMR. J Phys Chem B 2021; 125:4393-4408. [PMID: 33885309 DOI: 10.1021/acs.jpcb.0c10629] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The lyotropic phase behavior of four common and easily accessible glycosides, n-octyl α-d-glycosides, namely, α-Glc-OC8, α-Man-OC8, α-Gal-OC8, and α-Xyl-OC8, was investigated. The presence of normal hexagonal (HI), bicontinuous cubic (VI), and lamellar (Lα) phases in α-Glc-OC8 and α-Man-OC8 including their phase diagrams in water reported previously was verified by deuterium nuclear magnetic resonance (2H NMR), via monitoring the D2O spectra. Additionally, the partial binary phase diagrams and the liquid crystal structures formed by α-Gal-OC8 and α-Xyl-OC8 in D2O were constructed and confirmed using small- and wide-angle X-ray scattering and 2H NMR. The average number of bound water molecules (nb) per headgroup in the Lα phase was determined by the systematic measurement of the quadrupolar splitting of D2O over a wide range of molar ratio values (glycoside/D2O), especially at high glucoside composition. The number of bound water molecules bound to the headgroup was found to be around 1.5-2.0 for glucoside, mannoside, and galactoside, all of which possesses four OH groups. In the case of xyloside, which has only three OH groups, the bound water content is ∼2.0. Our findings confirmed that the bound water content of all n-octyl α-d-glycosides studied is lower compared to the number of possible hydrogen bonding sites possibly due to the fact that most of the OH groups are involved in intralayer interaction that holds the lipid assembly together.
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Affiliation(s)
- Wan Farah Nasuha Wan Iskandar
- Centre for Fundamental and Frontier Sciences in Nanostructure Self-Assembly, Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Malinda Salim
- Centre for Fundamental and Frontier Sciences in Nanostructure Self-Assembly, Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.,Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Melonney Patrick
- Centre for Fundamental and Frontier Sciences in Nanostructure Self-Assembly, Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Bakir A Timimi
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, U.K
| | - N Idayu Zahid
- Centre for Fundamental and Frontier Sciences in Nanostructure Self-Assembly, Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Rauzah Hashim
- Centre for Fundamental and Frontier Sciences in Nanostructure Self-Assembly, Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Abstract
Many efforts undertaken to study the solvation process have led to general theories that may describe mean properties, but are unable to provide a detailed understanding at the molecular level. Remarkably, the basic question of how many solvent molecules are necessary to solvate one solute molecule is still open. By exploring several water aggregates of increasing complexity, in this contribution we employ semiclassical spectroscopy to determine on quantum dynamical grounds the minimal network of surrounding water molecules to make the central one display the same vibrational features of liquid water. We find out that double-acceptor double-donor tetrahedral coordination constituting the standard picture is necessary but not sufficient, and that particular care must be reserved for the quantum description of the combination band due to the coupling of the central monomer bending mode with network librations. It is actually our ability to investigate the combination band with a quantum-derived approach that allows us to answer the titular question. The minimal structure eventually responsible for proper solvation is made of a total of 21 water molecules and includes two complete solvation shells, of which the whole first one is tetrahedrally coordinated to the central molecule. How quantum spectroscopic simulations can explain water solvation by comparison with experimental spectra.![]()
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Affiliation(s)
- Alessandro Rognoni
- Dipartimento di Chimica, Università degli Studi di Milano Via Golgi 19 20133 Milano Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano Via Golgi 19 20133 Milano Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano Via Golgi 19 20133 Milano Italy
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Cho BH, Chung W, Nam BH. Molecular Dynamics Simulation of Calcium-Silicate-Hydrate for Nano-Engineered Cement Composites-A Review. NANOMATERIALS 2020; 10:nano10112158. [PMID: 33138107 PMCID: PMC7693929 DOI: 10.3390/nano10112158] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 01/01/2023]
Abstract
With the continuous research efforts, sophisticated predictive molecular dynamics (MD) models for C-S-H have been developed, and the application of MD simulation has been expanded from fundamental understanding of C-S-H to nano-engineered cement composites. This paper comprehensively reviewed the current state of MD simulation on calcium-silicate-hydrate (C-S-H) and its diverse applications to nano-engineered cement composites, including carbon-based nanomaterials (i.e., carbon nanotube, graphene, graphene oxide), reinforced cement, cement–polymer nanocomposites (with an application on 3D printing concrete), and chemical additives for improving environmental resistance. In conclusion, the MD method could not only compute but also visualize the nanoscale behaviors of cement hydrates and other ingredients in the cement matrix; thus, fundamental properties of C-S-H structure and its interaction with nanoparticles can be well understood. As a result, the MD enabled us to identify and evaluate the performance of new advanced nano-engineered cement composites.
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Affiliation(s)
- Byoung Hooi Cho
- Department of Civil, Environmental and Construction Engineering, University of Central Florida, 12800 Pegasus Drive, Suite 211, Orlando, FL 32816, USA
| | - Wonseok Chung
- Department of Civil Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin-si 17104, Korea
| | - Boo Hyun Nam
- Department of Civil, Environmental and Construction Engineering, University of Central Florida, 12800 Pegasus Drive, Suite 211, Orlando, FL 32816, USA
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5
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Sakakura T, Murakami N, Takatsuji Y, Morimoto M, Haruyama T. Contribution of Discharge Excited Atomic N, N 2 *, and N 2 + to a Plasma/Liquid Interfacial Reaction as Suggested by Quantitative Analysis. Chemphyschem 2019; 20:1467-1474. [PMID: 30950156 DOI: 10.1002/cphc.201900212] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 03/29/2019] [Indexed: 11/07/2022]
Abstract
Electric-discharge nitrogen comprises three main types of excited nitrogen species-atomic nitrogen (Natom ), excited nitrogen molecules (N2 *), and nitrogen ions (N2 + ) - which have different lifetimes and reactivities. In particular, the interfacial reaction locus between the discharged nitrogen and the water phase produces nitrogen compounds such as ammonia and nitrate ions (denoted as N-compounds generically); this is referred to as the plasma/liquid interfacial (P/L) reaction. The Natom amount was analyzed quantitatively to clarify the contribution of Natom to the P/L reaction. We focused on the quantitative relationship between Natom and the produced N-compounds, and found that both N2 * and N2 + , which are active species other than Natom , contributed to P/L reaction. The production of N-compounds from N2 * and N2 + was enhanced upon UV irradiation of the water phase, but the production of N-compounds from Natom did not increase by UV irradiation. These results revealed that the P/L reactions starting from Natom and those starting from N2 * and N2 + follow different mechanisms.
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Affiliation(s)
- Tatsuya Sakakura
- Division of Functional Interface Engineering Department of Biological Functions and Engineering, Kyushu Institute of Technology, Kitakyushu Science and Research Park, Kitakyushu, Fukuoka, 808-0196, Japan
| | - Naoya Murakami
- Department of Applied Chemistry, Faculty of Engineering, Kyushu Institute of Technology 1-1 Sensuicho, Tobata, Kitakyushu, Fukuoka, 804-8550, Japan
| | - Yoshiyuki Takatsuji
- Division of Functional Interface Engineering Department of Biological Functions and Engineering, Kyushu Institute of Technology, Kitakyushu Science and Research Park, Kitakyushu, Fukuoka, 808-0196, Japan
| | - Masayuki Morimoto
- Division of Functional Interface Engineering Department of Biological Functions and Engineering, Kyushu Institute of Technology, Kitakyushu Science and Research Park, Kitakyushu, Fukuoka, 808-0196, Japan
| | - Tetsuya Haruyama
- Division of Functional Interface Engineering Department of Biological Functions and Engineering, Kyushu Institute of Technology, Kitakyushu Science and Research Park, Kitakyushu, Fukuoka, 808-0196, Japan
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6
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Imoto S, Marx D. Pressure response of the THz spectrum of bulk liquid water revealed by intermolecular instantaneous normal mode analysis. J Chem Phys 2019; 150:084502. [PMID: 30823759 DOI: 10.1063/1.5080381] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The radial distribution functions of liquid water are known to change significantly their shape upon hydrostatic compression from ambient conditions deep into the kbar pressure regime. It has been shown that despite their eye-catching changes, the fundamental locally tetrahedral fourfold H-bonding pattern that characterizes ambient water is preserved up to about 10 kbar (1 GPa), which is the stability limit of liquid water at 300 K. The observed increase in coordination number comes from pushing water molecules into the first coordination sphere without establishing an H-bond, resulting in roughly two such additional interstitial molecules at 10 kbar. THz spectroscopy has been firmly established as a powerful experimental technique to analyze H-bonding in aqueous solutions given that it directly probes the far-infrared lineshape and thus the prominent H-bond network mode around 180 cm-1. We, therefore, set out to assess pressure effects on the THz response of liquid water at 10 kbar in comparison to the 1 bar (0.1 MPa) reference, both at 300 K, with the aim to trace back the related lineshape changes to the structural level. To this end, we employ the instantaneous normal mode approximation to rigorously separate the H-bonding peak from the large background arising from the pronounced librational tail. By exactly decomposing the total molecular dynamics into hindered translations, hindered rotations, and intramolecular vibrations, we find that the H-bonding peak arises from translation-translation and translation-rotation correlations, which are successively decomposed down to the level of distinct local H-bond environments. Our utmost detailed analysis based on molecular pair classifications unveils that H-bonded double-donor water pairs contribute most to the THz response around 180 cm-1, whereas interstitial waters are negligible. Moreover, short double-donor H-bonds have their peak maximum significantly shifted toward higher frequencies with respect to such long H-bonds. In conjunction with an increasing relative population of these short H-bonds versus the long ones (while the population of other water pair classes is essentially pressure insensitive), this explains not only the blue-shift of the H-bonding peak by about 20-30 cm-1 in total from 1 bar to 10 kbar but also the filling of the shallow local minimum of the THz lineshape located in between the network peak and the red-wing of the librational band at 1 bar. Based on the changing populations as a function of pressure, we are also able to roughly estimate the pressure-dependence of the H-bond network mode and find that its pressure response and thus the blue-shifting are most pronounced at low kbar pressures.
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Affiliation(s)
- Sho Imoto
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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7
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Affiliation(s)
- Kun Dong
- State Key Laboratory of Multiphase
Complex Systems, Beijing Key Laboratory of Ionic Liquids Clean Process,
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiaomin Liu
- State Key Laboratory of Multiphase
Complex Systems, Beijing Key Laboratory of Ionic Liquids Clean Process,
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Haifeng Dong
- State Key Laboratory of Multiphase
Complex Systems, Beijing Key Laboratory of Ionic Liquids Clean Process,
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiangping Zhang
- State Key Laboratory of Multiphase
Complex Systems, Beijing Key Laboratory of Ionic Liquids Clean Process,
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Suojiang Zhang
- State Key Laboratory of Multiphase
Complex Systems, Beijing Key Laboratory of Ionic Liquids Clean Process,
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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8
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Muñoz-Santiburcio D, Marx D. On the complex structural diffusion of proton holes in nanoconfined alkaline solutions within slit pores. Nat Commun 2016; 7:12625. [PMID: 27550616 PMCID: PMC4996981 DOI: 10.1038/ncomms12625] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 07/19/2016] [Indexed: 11/24/2022] Open
Abstract
The hydroxide anion OH−(aq) in homogeneous bulk water, that is, the solvated proton hole, is known to feature peculiar properties compared with excess protons solvated therein. In this work, it is disclosed that nanoconfinement of such alkaline aqueous solutions strongly affects the key structural and dynamical properties of OH−(aq) compared with the bulk limit. The combined effect of the preferred hypercoordinated solvation pattern of OH−(aq), its preferred perpendicular orientation relative to the confining surfaces, the pronounced layering of nanoconfined water and the topology of the hydrogen bond network required for proton hole transfer lead to major changes of the charge transport mechanism, in such a way that the proton hole migration mechanism depends exquisitely on the width of the confined space that hosts the water film. Moreover, the anionic Zundel complex, which is of transient nature in homogeneous bulk solutions, can be dynamically trapped as a shallow intermediate species by suitable nanoconfinement conditions. Confined liquids can exhibit very different properties compared with the bulk. Here, the authors show that the migration mechanism of the hydroxide anion in water is greatly affected by bi-dimensional nano-confinement and strongly depends on the width of the confined space.
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Affiliation(s)
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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9
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Wilson HF, Barnard AS. Water bilayers on ZnO(101̄0) surfaces: data-driven structural search. RSC Adv 2016. [DOI: 10.1039/c5ra26874e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We demonstrate an approach for the use of data science methods for structural search for high-stability atomic structures in ab initio simulation, via the analysis of a large set of candidate structures.
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Affiliation(s)
- Hugh F. Wilson
- CSIRO Virtual Nanoscience Laboratory
- Australia
- Department of Applied Physics
- RMIT University
- Melbourne
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10
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Natarajan SK, Behler J. Neural network molecular dynamics simulations of solid–liquid interfaces: water at low-index copper surfaces. Phys Chem Chem Phys 2016; 18:28704-28725. [DOI: 10.1039/c6cp05711j] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Molecular dynamics simulation of the water–copper interface have been carried out using high-dimensional neural network potential based on density functional theory.
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Affiliation(s)
| | - Jörg Behler
- Lehrstuhl für Theoretische Chemie
- Ruhr-Universität Bochum
- D-44780 Bochum
- Germany
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11
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Sarangi NK, Ramesh N, Patnaik A. Structure and dynamics of H2O vis-á-vis phenylalanine recognition at a DPPC lipid membrane via interfacial H-bond types: insights from polarized FT-IRRAS and ADMP simulations. J Chem Phys 2015; 142:024702. [PMID: 25591372 DOI: 10.1063/1.4905075] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Preferential and enantioselective interactions of L-/D-Phenylalanine (L-Phe and D-Phe) and butoxycarbonyl-protected L-/D-Phenylalanine (LPA and DPA) as guest with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (L-DPPC) as host were tapped by using real time Fourier transform infrared reflection absorption spectroscopy (FT-IRRAS). Polarization-modulated FT-IRRAS of DPPC monolayers above the phenylalanine modified subphases depicted fine structure/conformation differences under considerations of controlled 2D surface pressure. Selective molecular recognition of D-enantiomer over L-enantiomer driven by the DPPC head group via H-bonding and electrostatic interactions was evident spectroscopically. Accordingly, binding constants (K) of 145, 346, 28, and 56 M(-1) for LPA, DPA, L-Phe, and D-Phe, respectively, were estimated. The real time FT-IRRAS water bands were strictly conformation sensitive. The effect of micro-solvation on the structure and stability of the 1:1 diastereomeric L-lipid⋯, LPA/DPA and L-lipid⋯, (L/D)-Phe adducts was investigated with the aid of Atom-centered Density Matrix Propagation (ADMP), a first principle quantum mechanical molecular dynamics approach. The phosphodiester fragment was the primary site of hydration where specific solvent interactions were simulated through single- and triple- "water-phosphate" interactions, as water cluster's "tetrahedral dice" to a "trimeric motif" transformation as a partial de-clusterization was evident. Under all the hydration patterns considered in both static and dynamic descriptions of density functional theory, L-lipid/D-amino acid enantiomer adducts continued to be stable structures while in dynamic systems, water rearranged without getting "squeezed-out" in the process of recognition. In spite of the challenging computational realm of this multiscale problem, the ADMP simulated molecular interactions complying with polarized vibrational spectroscopy unraveled a novel route to chiral recognition and interfacial water structure.
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Affiliation(s)
- Nirod Kumar Sarangi
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | - Nivarthi Ramesh
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | - Archita Patnaik
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
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12
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Lórenz-Fonfría VA, Muders V, Schlesinger R, Heberle J. Changes in the hydrogen-bonding strength of internal water molecules and cysteine residues in the conductive state of channelrhodopsin-1. J Chem Phys 2015; 141:22D507. [PMID: 25494778 DOI: 10.1063/1.4895796] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Water plays an essential role in the structure and function of proteins, particularly in the less understood class of membrane proteins. As the first of its kind, channelrhodopsin is a light-gated cation channel and paved the way for the new and vibrant field of optogenetics, where nerve cells are activated by light. Still, the molecular mechanism of channelrhodopsin is not understood. Here, we applied time-resolved FT-IR difference spectroscopy to channelrhodopsin-1 from Chlamydomonas augustae. It is shown that the (conductive) P2(380) intermediate decays with τ ≈ 40 ms and 200 ms after pulsed excitation. The vibrational changes between the closed and the conductive states were analyzed in the X-H stretching region (X = O, S, N), comprising vibrational changes of water molecules, sulfhydryl groups of cysteine side chains and changes of the amide A of the protein backbone. The O-H stretching vibrations of "dangling" water molecules were detected in two different states of the protein using H2 (18)O exchange. Uncoupling experiments with a 1:1 mixture of H2O:D2O provided the natural uncoupled frequencies of the four O-H (and O-D) stretches of these water molecules, each with a very weakly hydrogen-bonded O-H group (3639 and 3628 cm(-1)) and with the other O-H group medium (3440 cm(-1)) to moderately strongly (3300 cm(-1)) hydrogen-bonded. Changes in amide A and thiol vibrations report on global and local changes, respectively, associated with the formation of the conductive state. Future studies will aim at assigning the respective cysteine group(s) and at localizing the "dangling" water molecules within the protein, providing a better understanding of their functional relevance in CaChR1.
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Affiliation(s)
| | - Vera Muders
- Genetic Biophysics, Freie Universität Berlin, 14195 Berlin, Germany
| | | | - Joachim Heberle
- Experimental Molecular Biophysics, Freie Universität Berlin, 14195 Berlin, Germany
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13
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Kessler J, Elgabarty H, Spura T, Karhan K, Partovi-Azar P, Hassanali AA, Kühne TD. Structure and Dynamics of the Instantaneous Water/Vapor Interface Revisited by Path-Integral and Ab Initio Molecular Dynamics Simulations. J Phys Chem B 2015; 119:10079-86. [DOI: 10.1021/acs.jpcb.5b04185] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jan Kessler
- Institute
of Physical Chemistry and Center of Computational Sciences, Johannes Gutenberg University Mainz, Staudinger Weg 9, D-55128 Mainz, Germany
| | - Hossam Elgabarty
- Institute
of Physical Chemistry and Center of Computational Sciences, Johannes Gutenberg University Mainz, Staudinger Weg 9, D-55128 Mainz, Germany
| | - Thomas Spura
- Dynamics
of Condensed Matter, Department of Chemistry, University of Paderborn, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Kristof Karhan
- Dynamics
of Condensed Matter, Department of Chemistry, University of Paderborn, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Pouya Partovi-Azar
- Dynamics
of Condensed Matter, Department of Chemistry, University of Paderborn, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Ali A. Hassanali
- The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34151 Trieste, Italy
| | - Thomas D. Kühne
- Dynamics
of Condensed Matter, Department of Chemistry, University of Paderborn, Warburger Str. 100, D-33098 Paderborn, Germany
- Paderborn Center for Parallel Computing and Institute for Lightweight Design with Hybrid Systems, Warburger Str. 100, D-33098 Paderborn, Germany
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14
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Pyta K, Przybylski P, Bartl F. Regioselective long-range proton transfer in new rifamycin antibiotics: a process in which crown ethers act as stronger Brønsted bases than amines. Chemphyschem 2015; 16:938-42. [PMID: 25639734 DOI: 10.1002/cphc.201402892] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Indexed: 01/10/2023]
Abstract
Water-mediated proton transfer in six new derivatives of 3-formylrifamycin SV that contain crown, aza-crown, and benzo-crown ether rings were investigated by FTIR and NMR spectroscopy. (1)H-(1)H COSY couplings provide evidence for the formation of zwitterionic structures of the aza-crown and crown ether derivatives of rifamycin, in which a proton from one of the phenolic groups is transferred to tertiary and secondary nitrogen atoms. The increased intensity of the continuous absorption in the mid-infrared region together with the NMR data indicate proton transfer from the phenol group of the rifamycin core to the cavity of the benzo-crown ether ring. This proton transfer is achieved by formation of hydronium (H3O(+)) or Zundel ions (H5O2(+)), which form intermolecular hydrogen bonds with the oxygen atoms of the crown ether. DFT calculations are in agreement with the spectroscopic data and allow visualization of the structures of all new rifamycin derivatives, characterized by different intramolecular protonation sites.
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Affiliation(s)
- Krystian Pyta
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznan (Poland)
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15
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Imoto S, Forbert H, Marx D. Water structure and solvation of osmolytes at high hydrostatic pressure: pure water and TMAO solutions at 10 kbar versus 1 bar. Phys Chem Chem Phys 2015; 17:24224-37. [DOI: 10.1039/c5cp03069b] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Solvation structures of trimethylamine N-oxide change drastically due to the increase in the hydrostatic pressure.
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Affiliation(s)
- Sho Imoto
- Ruhr-Universität Bochum
- D-44780 Bochum
- Germany
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16
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Cipcigan FS, Sokhan VP, Jones AP, Crain J, Martyna GJ. Hydrogen bonding and molecular orientation at the liquid–vapour interface of water. Phys Chem Chem Phys 2015; 17:8660-9. [DOI: 10.1039/c4cp05506c] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We discover two hydrogen bonding motifs in liquid water and a related asymmetry linked with molecular orientation at its liquid–vapour interface.
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Affiliation(s)
- Flaviu S. Cipcigan
- School of Physics and Astronomy
- University of Edinburgh
- Edinburgh EH9 3JZ
- UK
| | | | - Andrew P. Jones
- School of Physics and Astronomy
- University of Edinburgh
- Edinburgh EH9 3JZ
- UK
- National Physical Laboratory
| | - Jason Crain
- School of Physics and Astronomy
- University of Edinburgh
- Edinburgh EH9 3JZ
- UK
- National Physical Laboratory
| | - Glenn J. Martyna
- School of Physics and Astronomy
- University of Edinburgh
- Edinburgh EH9 3JZ
- UK
- IBM T. J. Watson Research Center
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17
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Karhan K, Khaliullin RZ, Kühne TD. On the role of interfacial hydrogen bonds in “on-water” catalysis. J Chem Phys 2014; 141:22D528. [DOI: 10.1063/1.4902537] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Kristof Karhan
- Department of Chemistry, University of Paderborn, Warburger Str. 100, D-33098 Paderborn, Germany
- Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Staudinger Weg 7, D-55128 Mainz, Germany
| | - Rustam Z. Khaliullin
- Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Staudinger Weg 7, D-55128 Mainz, Germany
| | - Thomas D. Kühne
- Department of Chemistry, University of Paderborn, Warburger Str. 100, D-33098 Paderborn, Germany
- Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Staudinger Weg 7, D-55128 Mainz, Germany
- Center for Computational Sciences, Johannes Gutenberg University Mainz, D-55128 Mainz, Germany
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18
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Dong K, Song Y, Liu X, Cheng W, Yao X, Zhang S. Understanding Structures and Hydrogen Bonds of Ionic Liquids at the Electronic Level. J Phys Chem B 2012; 116:1007-17. [DOI: 10.1021/jp205435u] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kun Dong
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Yuting Song
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Xiaomin Liu
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Weiguo Cheng
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Xiaoqian Yao
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Suojiang Zhang
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
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19
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Max JJ, Chapados C. Isotope effects in liquid water by infrared spectroscopy. V. A sea of OH4ofC2vsymmetry. J Chem Phys 2011; 134:164502. [PMID: 21528968 DOI: 10.1063/1.3581035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jean-Joseph Max
- Département de chimie-biologie, Université du Québec à Trois-Rivières, Trois-Rivières, Québec G9A 5H7, Canada.
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20
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Tuckerman ME, Chandra A, Marx D. A statistical mechanical theory of proton transport kinetics in hydrogen-bonded networks based on population correlation functions with applications to acids and bases. J Chem Phys 2011; 133:124108. [PMID: 20886925 DOI: 10.1063/1.3474625] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Extraction of relaxation times, lifetimes, and rates associated with the transport of topological charge defects in hydrogen-bonded networks from molecular dynamics simulations is a challenge because proton transfer reactions continually change the identity of the defect core. In this paper, we present a statistical mechanical theory that allows these quantities to be computed in an unbiased manner. The theory employs a set of suitably defined indicator or population functions for locating a defect structure and their associated correlation functions. These functions are then used to develop a chemical master equation framework from which the rates and lifetimes can be determined. Furthermore, we develop an integral equation formalism for connecting various types of population correlation functions and derive an iterative solution to the equation, which is given a graphical interpretation. The chemical master equation framework is applied to the problems of both hydronium and hydroxide transport in bulk water. For each case it is shown that the theory establishes direct links between the defect's dominant solvation structures, the kinetics of charge transfer, and the mechanism of structural diffusion. A detailed analysis is presented for aqueous hydroxide, examining both reorientational time scales and relaxation of the rotational anisotropy, which is correlated with recent experimental results for these quantities. Finally, for OH(-)(aq) it is demonstrated that the "dynamical hypercoordination mechanism" is consistent with available experimental data while other mechanistic proposals are shown to fail. As a means of going beyond the linear rate theory valid from short up to intermediate time scales, a fractional kinetic model is introduced in the Appendix in order to describe the nonexponential long-time behavior of time-correlation functions. Within the mathematical framework of fractional calculus the power law decay ∼t(-σ), where σ is a parameter of the model and depends on the dimensionality of the system, is obtained from Mittag-Leffler functions due to their long-time asymptotics, whereas (stretched) exponential behavior is found for short times.
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Affiliation(s)
- Mark E Tuckerman
- Department of Chemistry and Courant Institute of Mathematical Sciences, New York University, New York, New York 10003, USA.
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21
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Malenkov GG. Structure and dynamics of surfaces of thin films and water microdroplets. COLLOID JOURNAL 2010. [DOI: 10.1134/s1061933x1005011x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Dissecting the THz spectrum of liquid water from first principles via correlations in time and space. Proc Natl Acad Sci U S A 2010; 107:12068-73. [PMID: 20566886 DOI: 10.1073/pnas.0914885107] [Citation(s) in RCA: 301] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Solvation of molecules in water is at the heart of a myriad of molecular phenomena and of crucial importance to understanding such diverse issues as chemical reactivity or biomolecular function. Complementing well-established approaches, it has been shown that laser spectroscopy in the THz frequency domain offers new insights into hydration from small solutes to proteins. Upon introducing spatially-resolved analyses of the absorption cross section by simulations, the sensitivity of THz spectroscopy is traced back to characteristic distance-dependent modulations of absorption intensities for bulk water. The prominent peak at approximately 200 cm(-1) is dominated by first-shell dynamics, whereas a concerted motion involving the second solvation shell contributes most significantly to the absorption at about 80 cm(-1) approximately 2.4 THz. The latter can be understood in terms of an umbrella-like motion of two hydrogen-bonded tetrahedra along the connecting hydrogen bond axis. Thus, a modification of the hydrogen bond network, e.g., due to the presence of a solute, is expected to affect vibrational motion and THz absorption intensity at least on a length scale that corresponds to two layers of solvating water molecules. This result provides a molecular mechanism explaining the experimentally determined sensitivity of absorption changes in the THz domain in terms of distinct, solute-induced dynamical properties in solvation shells of (bio)molecules--even in the absence of well-defined resonances.
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23
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Chai BH, Zheng JM, Zhao Q, Pollack GH. Spectroscopic Studies of Solutes in Aqueous Solution. J Phys Chem A 2008; 112:2242-7. [DOI: 10.1021/jp710105n] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bing-hua Chai
- Department of Bioengineering, Box 355061, University of Washington, Seattle, Washington 98195
| | - Jian-ming Zheng
- Department of Bioengineering, Box 355061, University of Washington, Seattle, Washington 98195
| | - Qing Zhao
- Department of Bioengineering, Box 355061, University of Washington, Seattle, Washington 98195
| | - Gerald H. Pollack
- Department of Bioengineering, Box 355061, University of Washington, Seattle, Washington 98195
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24
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Marx D. Proton transfer 200 years after von Grotthuss: insights from ab initio simulations. Chemphyschem 2007; 7:1848-70. [PMID: 16929553 DOI: 10.1002/cphc.200600128] [Citation(s) in RCA: 610] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In the last decade, ab initio simulations and especially Car-Parrinello molecular dynamics have significantly contributed to the improvement of our understanding of both the physical and chemical properties of water, ice, and hydrogen-bonded systems in general. At the heart of this family of in silico techniques lies the crucial idea of computing the many-body interactions by solving the electronic structure problem "on the fly" as the simulation proceeds, which circumvents the need for pre-parameterized potential models. In particular, the field of proton transfer in hydrogen-bonded networks greatly benefits from these technical advances. Here, several systems of seemingly quite different nature and of increasing complexity, such as Grotthuss diffusion in water, excited-state proton-transfer in solution, phase transitions in ice, and protonated water networks in the membrane protein bacteriorhodopsin, are discussed in the realms of a unifying viewpoint.
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Affiliation(s)
- Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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25
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Brodsky AM, Mitchell GT, Ziegler SL, Burgess LW. Coherence loss in light backscattering by random media with nanoscale nonuniformities. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 75:046605. [PMID: 17501005 DOI: 10.1103/physreve.75.046605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Indexed: 05/15/2023]
Abstract
An experimental technique for measuring time-resolved coherence loss and destruction of backscattered wave packets in random media is described. The results of such measurements, performed with a modified Michelson interferometer, contain rich information about the characteristics of media nonuniformities. Experimental data for model nanosuspensions are compared with theoretical expressions developed in the paper which include the effects of Mie-type resonant scattering. We attribute one such observed effect to enhanced ineleastic optical transitions near the surface of nonmetallic nanoparticles. The inverse problem of characterization of multiscattering random media by backscattering is also considered.
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Affiliation(s)
- Anatol M Brodsky
- Center for Process Analytical Chemistry, Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
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26
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Abstract
The 500 MHz NMR spectra of water-benzene solution near saturation at 303.15, 323.15, and 343.15 K indicate that there is a proton-proton exchange between the water and benzene molecules. In the solution water appears to be present as a dimer attached to the benzene pi cloud on one side of each of the two (initially degenerate) fundamental energy levels, as predicted by the Jahn-Teller effect. This view is reinforced by the fact that one of its hydrogen atoms hovers above one of the carbon atoms and the other three are spread upward around the C6 axis of the benzene molecule. It is also supported by the calculated NMR spectra. Both effects are responsible for the change in the NMR spectra of the water molecules from a single line into four AB signals.
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Affiliation(s)
- Maximo Baron
- Facultad de Ciencias Exactas y Naturales, Universidad de Belgrano, Buenos Aires, Argentina.
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27
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Shen YR, Ostroverkhov V. Sum-Frequency Vibrational Spectroscopy on Water Interfaces: Polar Orientation of Water Molecules at Interfaces. Chem Rev 2006; 106:1140-54. [PMID: 16608175 DOI: 10.1021/cr040377d] [Citation(s) in RCA: 674] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yuen Ron Shen
- Department of Physics, University of California, Berkeley, California 94720, USA.
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28
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Affiliation(s)
- Bernd Winter
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany.
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29
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30
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Mundy CJ, Kuo IFW. First-Principles Approaches to the Structure and Reactivity of Atmospherically Relevant Aqueous Interfaces. Chem Rev 2006; 106:1282-304. [PMID: 16608181 DOI: 10.1021/cr040375t] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christopher J Mundy
- Computational Chemistry and Chemical Biology, Chemistry and Materials Science, Lawrence Livermore National Laboratory, PO Box 808, Livermore, CA 94551, USA.
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31
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Meyer B, Rabaa H, Marx D. Water adsorption on ZnO(101̄0): from single molecules to partially dissociated monolayers. Phys Chem Chem Phys 2006; 8:1513-20. [PMID: 16633635 DOI: 10.1039/b515604a] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Static and dynamic density functional calculations have been used to study the structure and energetics of water adsorbed on the main cleavage plane of ZnO. In the single molecule limit we find that molecular adsorption is strongly preferred. The water binding energy increases for higher coverages due to an almost isotropic attractive water-water interaction which leads to clustering and formation of monolayer islands in the low water coverage regime. A thermodynamic analysis further shows that the full water monolayer is clearly the most stable phase until water starts to desorb. The water monolayer is even more stabilized by a partial dissociation of the water molecules, yielding as most stable configuration a (2x1) superstructure where every second water molecule is cleaved. The dissociation barrier for this process is very small which allows for an auto-dissociation of the water molecules even at low temperatures as observed experimentally. Finally we find that the energy cost involved to form [1210]-oriented domain boundaries between (2x1) patches with different orientation is almost negligible which explains the abundance of such domain boundaries in STM images.
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Affiliation(s)
- Bernd Meyer
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany
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32
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Krishnan C, Garnett M. New insights into the double layer structure from impedance measurements: Implications for biological systems. Electrochim Acta 2006. [DOI: 10.1016/j.electacta.2005.02.133] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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33
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Garczarek F, Gerwert K. Functional waters in intraprotein proton transfer monitored by FTIR difference spectroscopy. Nature 2005; 439:109-12. [PMID: 16280982 DOI: 10.1038/nature04231] [Citation(s) in RCA: 419] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Accepted: 09/08/2005] [Indexed: 11/09/2022]
Abstract
Much progress has been made in our understanding of water molecule reactions on surfaces, proton solvation in gas-phase water clusters and proton transfer through liquids. Compared with our advanced understanding of these physico-chemical systems, much less is known about individual water molecules and their cooperative behaviour in heterogeneous proteins during enzymatic reactions. Here we use time-resolved Fourier transform infrared spectroscopy (trFTIR) and in situ H2(18)O/H2(16)O exchange FTIR to determine how the membrane protein bacteriorhodopsin uses the interplay among strongly hydrogen-bonded water molecules, a water molecule with a dangling hydroxyl group and a protonated water cluster to transfer protons. The precise arrangement of water molecules in the protein matrix results in a controlled Grotthuss proton transfer, in contrast to the random proton migration that occurs in liquid water. Our findings support the emerging paradigm that intraprotein water molecules are as essential for biological functions as amino acids.
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Affiliation(s)
- Florian Garczarek
- Lehrstuhl für Biophysik, Ruhr-Universität Bochum, D-44780 Bochum, Germany
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34
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Schravendijk P, van der Vegt N, Delle Site L, Kremer K. Dual-Scale Modeling of Benzene Adsorption onto Ni(111) and Au(111) Surfaces in Explicit Water. Chemphyschem 2005; 6:1866-71. [PMID: 16086342 DOI: 10.1002/cphc.200400591] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We present a multiscale modeling approach for studying interactions of organic molecules with metal surfaces in explicit water. The approach is based on combining adsorption energies of isolated molecules on transition metal surfaces calculated by ab initio density functional methods and classical molecular dynamics simulations using atomistically detailed force fields. The interaction of benzene with Ni(111) and Au(111) surfaces was studied. It is shown that a strong affinity of water for the hydrophilic surfaces makes benzene adsorption on Au thermodynamically unfavorable, while on Ni there is no preference. The work presented here serves as a first step in modeling the interactions of larger organic molecules with metal surfaces.
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Affiliation(s)
- Pim Schravendijk
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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35
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Ostroverkhov V, Waychunas GA, Shen YR. New information on water interfacial structure revealed by phase-sensitive surface spectroscopy. PHYSICAL REVIEW LETTERS 2005; 94:046102. [PMID: 15783575 DOI: 10.1103/physrevlett.94.046102] [Citation(s) in RCA: 267] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2004] [Indexed: 05/11/2023]
Abstract
A phase-sensitive sum-frequency vibrational spectroscopic technique is developed to study interfacial water structure of water/quartz interfaces. Measurements allow deduction of both real and imaginary parts of the surface nonlinear spectral response, revealing an unprecedentedly detailed picture of the net polar orientations of the water species at the interface. The orientations of the icelike and liquidlike species appear to respond very differently to the bulk pH change indicating the existence of different surface sites on quartz with different deprotonation pK values.
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Affiliation(s)
- Victor Ostroverkhov
- Department of Physics, University of California, Berkeley, California 94720, USA
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36
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Abstract
Insight into the boiling of water is obtained from molecular dynamics simulations. The process is initiated by the spontaneous formation of small vacuum cavities in liquid water. By themselves, these defects are very short lived. If, however, several cavities occur at close distances, they are likely to merge into larger vacuum holes. At the liquid-vapor interfaces, single or small groups of water molecules tend to leave the liquid surface. Once the system is propagated beyond the transition state, these evaporation events outnumber the competing reintegration into the hydrogen-bonded network.
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Affiliation(s)
- Dirk Zahn
- Max-Planck Institut für Chemische Physik fester Stoffe, Nöthnitzer Strasse 40, 01187 Dresden, Germany.
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