1
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Kacenauskaite L, Moncada Cohen M, Van Wyck SJ, Fayer MD. Fast Structural Dynamics in Concentrated HCl Solutions: From Proton Hopping to the Bulk Viscosity. J Am Chem Soc 2024; 146:12355-12364. [PMID: 38682723 DOI: 10.1021/jacs.3c11620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
Concentrated acid solutions, particularly HCl, have been studied extensively to examine the proton hopping and infrared spectral signatures of hydronium ions. Much less attention has been given to the structural dynamics of concentrated HCl solutions. Here, we apply optical heterodyne detected-optical Kerr effect (OHD-OKE) measurements to examine HCl concentration-dependent dynamics from moderate (0.8 m) to very high (15.5 m) concentrations and compare the results to the dynamics of NaCl solutions, as Na+ is similar in size to the hydronium cation. Both HCl and NaCl OHD-OKE signals decay as triexponentials at all concentrations, in contrast to pure water, which decays as a biexponential. Two remarkable features of the HCl dynamics are the following: (1) the bulk viscosity is linearly related to the slowest decay constant, t3, and (2) the concentration-dependent proton hopping times, determined by ab initio MD simulations and 2D IR chemical exchange experiments, both obtained from the literature, fall on the same line as the slowest structural dynamics relaxation time, t3, within experimental error. The structural dynamics of hydronium/chloride/water clusters, with relaxation times t3, are responsible for the concentration dependence of microscopic property of proton hopping and the macroscopic bulk viscosity. The slowest time constant (t3), which does not have a counterpart in pure water, is 3 ps at 0.8 m and increases by a factor of ∼2 by 15.5 m. The two fastest HCl decay constants, t1 and t2, are similar to those of pure water and increase mildly with the concentration.
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Affiliation(s)
- Laura Kacenauskaite
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
- Nano-Science Center & Department of Chemistry, University of Copenhagen, Copenhagen 2100, Denmark
| | - Max Moncada Cohen
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Stephen J Van Wyck
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Michael D Fayer
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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2
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Felsted RG, Graham TR, Zhao Y, Bazak JD, Nienhuis ET, Pauzauskie PJ, Joly AG, Pearce CI, Wang Z, Rosso KM. Anionic Effects on Concentrated Aqueous Lithium Ion Dynamics. J Phys Chem Lett 2024:5076-5087. [PMID: 38708887 DOI: 10.1021/acs.jpclett.4c00585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
The dynamics, orientational anisotropy, diffusivity, viscosity, and density were measured for concentrated lithium salt solutions, including lithium chloride (LiCl), lithium bromide (LiBr), lithium nitrite (LiNO2), and lithium nitrate (LiNO3), with methyl thiocyanate as an infrared vibrational probe molecule, using two-dimensional infrared spectroscopy (2D IR), nuclear magnetic resonance (NMR) spectroscopy, and viscometry. The 2D IR, NMR, and viscosity results show that LiNO2 exhibits longer correlation times, lower diffusivity, and nearly 4 times greater viscosity compared to those of the other lithium salt solutions of the same concentration, suggesting that nitrite anions may strongly facilitate structure formation via strengthening water-ion network interactions, directly impacting bulk solution properties at sufficiently high concentrations. Additionally, the LiNO2 and LiNO3 solutions show significantly weakened chemical interactions between the lithium cations and the methyl thiocyanate when compared with those of the lithium halide salts.
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Affiliation(s)
- Robert G Felsted
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Trent R Graham
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Yatong Zhao
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - J David Bazak
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Emily T Nienhuis
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Peter J Pauzauskie
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
- Materials Science and Engineering Department, University of Washington, Seattle, Washington 98195, United States
| | - Alan G Joly
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Carolyn I Pearce
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
- Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164, United States
| | - Zheming Wang
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Kevin M Rosso
- Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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3
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Ma R, Baradwaj N, Nomura KI, Krishnamoorthy A, Kalia RK, Nakano A, Vashishta P. Alkali hydroxide (LiOH, NaOH, KOH) in water: Structural and vibrational properties, including neutron scattering results. J Chem Phys 2024; 160:134309. [PMID: 38568947 DOI: 10.1063/5.0186058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 03/18/2024] [Indexed: 04/05/2024] Open
Abstract
Structural and vibrational properties of aqueous solutions of alkali hydroxides (LiOH, NaOH, and KOH) are computed using quantum molecular dynamics simulations for solute concentrations ranging between 1 and 10M. Element-resolved partial radial distribution functions, neutron and x-ray structure factors, and angular distribution functions are computed for the three hydroxide solutions as a function of concentration. The vibrational spectra and frequency-dependent conductivity are computed from the Fourier transforms of velocity autocorrelation and current autocorrelation functions. Our results for the structure are validated with the available neutron data for 17M concentration of NaOH in water [Semrouni et al., Phys. Chem. Chem. Phys. 21, 6828 (2019)]. We found that the larger ionic radius [rLi+
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Affiliation(s)
- Ruru Ma
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Nitish Baradwaj
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Ken-Ichi Nomura
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Aravind Krishnamoorthy
- Department of Mechanical Engineering, Texas A&M University, College Station, Texas 77843-3123, USA
| | - Rajiv K Kalia
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Aiichiro Nakano
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
| | - Priya Vashishta
- Collaboratory for Advanced Computing and Simulations, University of Southern California, Los Angeles, California 90007-0242, USA
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4
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Nienhuis ET, Pouvreau M, Graham TR, Prange MP, Page K, Loring JS, Stack AG, Clark AE, Schenter GK, Rosso KM, Pearce CI, Wang HW. Structure and reactivity of sodium aluminate complexes in alkaline solutions. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Kivelä H, Salomäki M, Vainikka P, Mäkilä E, Poletti F, Ruggeri S, Terzi F, Lukkari J. Effect of Water on a Hydrophobic Deep Eutectic Solvent. J Phys Chem B 2022; 126:513-527. [PMID: 35001628 PMCID: PMC8785191 DOI: 10.1021/acs.jpcb.1c08170] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 12/28/2021] [Indexed: 12/15/2022]
Abstract
Deep eutectic solvents (DESs) formed by hydrogen bond donors and acceptors are a promising new class of solvents. Both hydrophilic and hydrophobic binary DESs readily absorb water, making them ternary mixtures, and a small water content is always inevitable under ambient conditions. We present a thorough study of a typical hydrophobic DES formed by a 1:2 mole ratio of tetrabutyl ammonium chloride and decanoic acid, focusing on the effects of a low water content caused by absorbed water vapor, using multinuclear NMR techniques, molecular modeling, and several other physicochemical techniques. Already very low water contents cause dynamic nanoscale phase segregation, reduce solvent viscosity and fragility, increase self-diffusion coefficients and conductivity, and enhance local dynamics. Water interferes with the hydrogen-bonding network between the chloride ions and carboxylic acid groups by solvating them, which enhances carboxylic acid self-correlation and ion pair formation between tetrabutyl ammonium and chloride. Simulations show that the component molar ratio can be varied, with an effect on the internal structure. The water-induced changes in the physical properties are beneficial for most prospective applications but water creates an acidic aqueous nanophase with a high halide ion concentration, which may have chemically adverse effects.
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Affiliation(s)
- Henri Kivelä
- Department
of Chemistry, University of Turku, FI-20014 Turku, Finland
- Turku
University Centre for Surfaces and Materials (MatSurf), FI-20014 Turku, Finland
| | - Mikko Salomäki
- Department
of Chemistry, University of Turku, FI-20014 Turku, Finland
- Turku
University Centre for Surfaces and Materials (MatSurf), FI-20014 Turku, Finland
| | - Petteri Vainikka
- Department
of Chemistry, University of Turku, FI-20014 Turku, Finland
| | - Ermei Mäkilä
- Department
of Physics and Astronomy, University of
Turku, FI-20014 Turku, Finland
- Doctoral
School for Chemical and Physical Sciences, University of Turku, FI-20014 Turku, Finland
| | - Fabrizio Poletti
- Electrochemical
Sensors Group, Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi, 103, I-41125 Modena, Italy
| | - Stefano Ruggeri
- Electrochemical
Sensors Group, Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi, 103, I-41125 Modena, Italy
| | - Fabio Terzi
- Electrochemical
Sensors Group, Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi, 103, I-41125 Modena, Italy
| | - Jukka Lukkari
- Department
of Chemistry, University of Turku, FI-20014 Turku, Finland
- Turku
University Centre for Surfaces and Materials (MatSurf), FI-20014 Turku, Finland
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6
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Herbert JM, Paul SK. Interaction Energy Analysis of Monovalent Inorganic Anions in Bulk Water Versus Air/Water Interface. Molecules 2021; 26:6719. [PMID: 34771133 PMCID: PMC8588468 DOI: 10.3390/molecules26216719] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/29/2021] [Accepted: 11/03/2021] [Indexed: 11/16/2022] Open
Abstract
Soft anions exhibit surface activity at the air/water interface that can be probed using surface-sensitive vibrational spectroscopy, but the structural implications of this surface activity remain a matter of debate. Here, we examine the nature of anion-water interactions at the air/water interface using a combination of molecular dynamics simulations and quantum-mechanical energy decomposition analysis based on symmetry-adapted perturbation theory. Results are presented for a set of monovalent anions, including Cl-, Br-, I-, CN-, OCN-, SCN-, NO2-, NO3-, and ClOn- (n=1,2,3,4), several of which are archetypal examples of surface-active species. In all cases, we find that average anion-water interaction energies are systematically larger in bulk water although the difference (with respect to the same quantity computed in the interfacial environment) is well within the magnitude of the instantaneous fluctuations. Specifically for the surface-active species Br-(aq), I-(aq), ClO4-(aq), and SCN-(aq), and also for ClO-(aq), the charge-transfer (CT) energy is found to be larger at the interface than it is in bulk water, by an amount that is greater than the standard deviation of the fluctuations. The Cl-(aq) ion has a slightly larger CT energy at the interface, but NO3-(aq) does not; these two species are borderline cases where consensus is lacking regarding their surface activity. However, CT stabilization amounts to <20% of the total induction energy for each of the ions considered here, and CT-free polarization energies are systematically larger in bulk water in all cases. As such, the role of these effects in the surface activity of soft anions remains unclear. This analysis complements our recent work suggesting that the short-range solvation structure around these ions is scarcely different at the air/water interface from what it is in bulk water. Together, these observations suggest that changes in first-shell hydration structure around soft anions cannot explain observed surface activities.
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Affiliation(s)
- John M. Herbert
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, OH 43210, USA;
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7
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Liang J, Wei H, Yu K, Lin C, Li H, Ding M, Duan X. Structure and dynamics of ions in dipolar solvents: a coarse-grained simulation study. SOFT MATTER 2021; 17:6305-6314. [PMID: 34132314 DOI: 10.1039/d1sm00583a] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We employ the coarse-grained molecular dynamics simulation to investigate the fundamental structural and dynamic properties of the ionic solution with and without the application of an external electric field. Our simulations, in which the solvent molecules are treated as Stockmayer fluids and the ions are modeled as spheres, can effectively account for the multi-body correlations between ion-ion, ion-dipole, and dipole-dipole interactions, which are often ignored by the mean-field theories or coarse-grained simulations based on a dielectric continuum. By focusing on the coupling between effects of ion solvation, electrostatic correlations and applied electric field, we highlight some nontrivial microscopic molecular features of the systems, such as the reorganization of the dipolar solvent, clustering of the ions, and diffusions of ions and dipolar solvent molecules. Particularly, our simulation indicates the nonmonotonic dependence of the ionic clustering and ion diffusion rates on the dipolar nature of the solvent molecules, as well as the amplification of these tendencies caused by the electric field application. This work provides insights into the fundamental understanding of physicochemical properties for ion-containing liquids and contributes to the design and development of ion-containing materials.
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Affiliation(s)
- Jicai Liang
- Key Laboratory of Automobile Materials, Ministry of Education and College of Materials Science and Engineering, Jilin University, Changchun, Jilin 130025, China.
| | - Hao Wei
- Key Laboratory of Automobile Materials, Ministry of Education and College of Materials Science and Engineering, Jilin University, Changchun, Jilin 130025, China. and State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
| | - Kaifeng Yu
- Key Laboratory of Automobile Materials, Ministry of Education and College of Materials Science and Engineering, Jilin University, Changchun, Jilin 130025, China.
| | - Chengjiang Lin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China. and School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Hongfei Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China. and School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China
| | - Mingming Ding
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China.
| | - Xiaozheng Duan
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
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8
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Li Z, Chen Z, Hu J, Li H, Tian SX. A new experimental method for investigations on microstructure of liquid-vapor interface. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2101002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Ziyuan Li
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Ziwei Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Jie Hu
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Hao Li
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Shan Xi Tian
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
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9
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Qin H, Ma C, Gärtner S, Headen TF, Zuo T, Jiao G, Han Z, Imberti S, Han CC, Cheng H. Neutron total scattering investigation on the dissolution mechanism of trehalose in NaOH/urea aqueous solution. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2021; 8:014901. [PMID: 33644253 PMCID: PMC7889297 DOI: 10.1063/4.0000065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Trehalose is chosen as a model molecule to investigate the dissolution mechanism of cellulose in NaOH/urea aqueous solution. The combination of neutron total scattering and empirical potential structure refinement yields the most probable all-atom positions in the complex fluid and reveals the cooperative dynamic effects of NaOH, urea, and water molecules in the dissolution process. NaOH directly interacts with glucose rings by breaking the inter- and intra-molecular hydrogen bonding. Na+, thus, accumulates around electronegative oxygen atoms in the hydration shell of trehalose. Its local concentration is thereby 2-9 times higher than that in the bulk fluid. Urea molecules are too large to interpenetrate into trehalose and too complex to form hydrogen bonds with trehalose. They can only participate in the formation of the hydration shell around trehalose via Na+ bridging. As the main component in the complex fluid, water molecules have a disturbed tetrahedral structure in the presence of NaOH and urea. The structure of the mixed solvent does not change when it is cooled to -12 °C. This indicates that the dissolution may be a dynamic process, i.e., a competition between hydration shell formation and inter-molecule hydrogen bonding determines its dissolution. We, therefore, predict that alkali with smaller ions, such as LiOH, has better solubility for cellulose.
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Affiliation(s)
| | - Changli Ma
- Authors to whom correspondence should be addressed: and
| | - Sabrina Gärtner
- STFC ISIS Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Thomas F. Headen
- STFC ISIS Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | | | | | | | - Silvia Imberti
- STFC ISIS Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Charles C. Han
- Institute for Advanced Study, Shenzhen University, Shenzhen 508060, China
| | - He Cheng
- Authors to whom correspondence should be addressed: and
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10
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11
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Zhu F, Yamaguchi T, Yoshida K, Zhang W, Liu H, Zhou Y, Fang C. Ion hydration and association in aqueous potassium tetrahydroxyborate solutions. Analyst 2020; 145:2245-2255. [PMID: 31994541 DOI: 10.1039/c9an01662g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Potassium tetrahydroxyborate solution is a significant material in the borate solution family, but there is limited knowledge about hydration structures and interactions of K+, [B(OH)4-], and water. In this study, the X-ray diffraction measurements of potassium tetrahydroxyborate solutions have been made. The experimental structure factors are subjected to Empirical Potential Structure Refinement (EPSR) modeling to reveal the details of ion hydration and association in the aqueous solutions. This study shows that the O(W)-O(W) distance of water in the studied solutions ranges from 2.82 to 2.76 Å with a coordination number that ranges from 4.7 ± 1.4 to 3.1 ± 1.3 when the value of the water-salt molar ratio (WSR) is decreased from 30 to 6. The addition of ions slightly affects the tetrahedral structure of water even when the concentration of ions is high. The first hydration distance of K+ remained at ∼2.67 Å, whereas the value of the coordination number (CN) decreased from 5.4 ± 1.3 to 3.9 ± 1.5 when the concentration of the borate solution was increased. The hydration ability of K+ was weak and almost did not have a fixed local hydration structure. The pair distribution function (PDF) of gB-O(W)(r) shows that [B(OH)4-] has a broad hydration distance from 2.9 to 5.4 Å because of the complex interactive relationship between K+, [B(OH)4-] and water. There is a competitive hydration between K+ and [B(OH)4-]. Both the X-ray diffraction and DFT-based calculations confirm that the main species is monodentate contact ion pairs when WSR = 30, bidentate contact ion pairs when WSR = 14, and triple contact ion pairs when WSR = 6. These results will provide a new understanding about potassium tetrahydroxyborate solution.
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Affiliation(s)
- Fayan Zhu
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 81008, China
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12
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Di Gioacchino M, Ricci MA, Imberti S, Holzmann N, Bruni F. Hydration and aggregation of a simple amino acid: The case of glycine. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2019.112407] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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13
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Multistate Reactive Molecular Dynamics Simulations of Proton Diffusion in Water Clusters and in the Bulk. J Phys Chem B 2019; 123:9846-9861. [PMID: 31647873 DOI: 10.1021/acs.jpcb.9b03258] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The molecular mechanics with proton transfer (MMPT) force field is combined with multistate adiabatic reactive molecular dynamics (MS-ARMD) to describe proton transport in the condensed phase. Parametrization for small protonated water clusters based on electronic structure calculations at the MP2/6-311+G(2d,2p) level of theory and refinement by comparing with infrared spectra for a protonated water tetramer yields a force field which faithfully describes the minimum energy structures of small protonated water clusters. In protonated water clusters up to (H2O)100H+, the proton hopping rate is around 100 hops/ns. This rate converges for 21 ≤ n ≤ 31, and no further speedup in bulk water is found. This indicates that bulklike behavior requires the solvation of a Zundel motif by ∼25 water molecules, which corresponds to the second solvation sphere. For smaller cluster sizes, the number of available states (i.e., the number of proton acceptors) is too small and slows down proton-transfer rates. The cluster simulations confirm that the excess proton is typically located on the surface. The free-energy surface as a function of the weights of the two lowest states and a configurational parameter suggests that the "special pair" plays a central role in rapid proton transport. The barriers between this minimum-energy structure and the Zundel and Eigen minima are sufficiently low (∼1 kcal/mol, consistent with recent experiments and commensurate with a hopping rate of ∼100/ns or 1 every 10 ps), leading to a highly dynamic environment. These findings are also consistent with recent experiments which find that Zundel-type hydration geometries are prevalent in bulk water.
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14
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Bresnahan CG, David R, Milet A, Kumar R. Ion Pairing in HCl-Water Clusters: From Electronic Structure Investigations to Multiconfigurational Force-Field Development. J Phys Chem A 2019; 123:9371-9381. [PMID: 31589444 DOI: 10.1021/acs.jpca.9b07775] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the bulk, condensed-phase HCl exists as a dissociated Cl- ion and a proton that is delocalized over solvating water molecules. However, in the gas phase, HCl is covalent, and even on the introduction of hydrating water molecules, the HCl covalent state dominates small clusters and is relevant at larger clusters including 21 water molecules. Electronic structure calculations (at the MP2 level) and ab initio metadynamics simulations (at the DFT level) have been carried out on HCl-(H2O)n clusters with n = 2-22 to investigate distinct solvation environments in clusters from covalent HCl structure, to contact ion pairs and solvent-separated ion pairs. The data were further used to train and validate a multiconfigurational force-field for HCl-water clusters that incorporates covalent HCl states into the MS-EVB3.2 formalism. Additionally, the many-body interaction of the Cl- ion with water and the excess proton was modeled by the introduction of two geometric three-body terms that incorporates the dominant many-body interaction in an efficient noniterative manner.
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Affiliation(s)
- Caitlin G Bresnahan
- Department of Chemistry , 232 Choppin Hall , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Rolf David
- Department of Chemistry , 232 Choppin Hall , Louisiana State University , Baton Rouge , Louisiana 70803 , United States.,Univ. Grenoble Alpes, CNRS, DCM , 38000 Grenoble , France
| | - Anne Milet
- Univ. Grenoble Alpes, CNRS, DCM , 38000 Grenoble , France
| | - Revati Kumar
- Department of Chemistry , 232 Choppin Hall , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
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15
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Maeda N. Nucleation Curve of Carbon Dioxide Hydrate from a Linear Cooling Ramp Method. J Phys Chem A 2019; 123:7911-7919. [PMID: 31503494 DOI: 10.1021/acs.jpca.9b06633] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Formation of gas hydrate is a first-order phase transition that starts with nucleation. Understanding of nucleation is of interest to many in chemical and petroleum industries, as nucleation, while beneficial in many chemical processes, is detrimental in flow assurance of oil and natural gas pipelines. A primary difficulty in the investigation of gas hydrate nucleation has been the inability of researchers to compare nucleation rates of gas hydrates across various systems of different scales and complexities, which in turn has been limiting the ability of researchers to study the nucleation process itself. In this study, a first-generation high-pressure automated lag time apparatus (HP-ALTA MkI) was used to determine the nucleation curve of structure I (sI) - forming carbon dioxide hydrate. The instrument subjected a quiescent water sample of well-defined dimensions to a large number of linear cooling ramps under isobaric conditions, and detected and recorded carbon dioxide hydrate formation temperature distributions. A survival curve was constructed from the measured ensemble, and a nucleation curve was derived from the survival curve using the empirical model-independent method we had previously reported. The nucleation rate of carbon dioxide hydrate was found to be significantly greater than that of pure methane hydrate or that of natural gas hydrate over the entire range of subcooling investigated. We provide a new physical interpretation of an experimentally determined nucleation curve and, by doing so, solve one of the outstanding puzzles of the HP-ALTA technology.
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Affiliation(s)
- Nobuo Maeda
- Department of Civil & Environmental Engineering, School of Mining and Petroleum Engineering , University of Alberta , 7-207 Donadeo ICE, 9211-116 Street NW , Edmonton , AB T6G1H9 , Canada
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16
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17
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Yuan R, Napoli JA, Yan C, Marsalek O, Markland TE, Fayer MD. Tracking Aqueous Proton Transfer by Two-Dimensional Infrared Spectroscopy and ab Initio Molecular Dynamics Simulations. ACS CENTRAL SCIENCE 2019; 5:1269-1277. [PMID: 31403075 PMCID: PMC6661862 DOI: 10.1021/acscentsci.9b00447] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Indexed: 05/26/2023]
Abstract
Proton transfer in water is ubiquitous and a critical elementary event that, via proton hopping between water molecules, enables protons to diffuse much faster than other ions. The problem of the anomalous nature of proton transport in water was first identified by Grotthuss over 200 years ago. In spite of a vast amount of modern research effort, there are still many unanswered questions about proton transport in water. An experimental determination of the proton hopping time has remained elusive due to its ultrafast nature and the lack of direct experimental observables. Here, we use two-dimensional infrared spectroscopy to extract the chemical exchange rates between hydronium and water in acid solutions using a vibrational probe, methyl thiocyanate. Ab initio molecular dynamics (AIMD) simulations demonstrate that the chemical exchange is dominated by proton hopping. The observed experimental and simulated acid concentration dependence then allow us to extrapolate the measured single step proton hopping time to the dilute limit, which, within error, gives the same value as inferred from measurements of the proton mobility and NMR line width analysis. In addition to obtaining the proton hopping time in the dilute limit from direct measurements and AIMD simulations, the results indicate that proton hopping in dilute acid solutions is induced by the concerted multi-water molecule hydrogen bond rearrangement that occurs in pure water. This proposition on the dynamics that drive proton hopping is confirmed by a combination of experimental results from the literature.
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Affiliation(s)
- Rongfeng Yuan
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Joseph A. Napoli
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Chang Yan
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Ondrej Marsalek
- Charles
University, Faculty of Mathematics and Physics, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
| | - Thomas E. Markland
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Michael D. Fayer
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
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18
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Semrouni D, Wang HW, Clark SB, Pearce CI, Page K, Schenter G, Wesolowski DJ, Stack AG, Clark AE. Resolving local configurational contributions to X-ray and neutron radial distribution functions within solutions of concentrated electrolytes - a case study of concentrated NaOH. Phys Chem Chem Phys 2019; 21:6828-6838. [PMID: 30620014 DOI: 10.1039/c8cp06802j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Extreme conditions of complex materials often lead to a manifold of local environments that challenge characterization and require new advances at the intersection of modern experimental and theoretical techniques. In this contribution, highly caustic and viscous aqueous NaOD solutions were characterized with a combination of X-ray and neutron radial distribution function (RDF) analyses, molecular dynamics simulations and sub-ensemble analysis. While this system has been the topic of some study, the current work expands upon the state of knowledge regarding the extent to which water is perturbed within this chemically extreme solution. Further, we introduce analyses that goes beyond merely identifying the different local environments (ion solvation and coordination environments) that are present, but toward understanding their relative contributions to the ensemble solution RDF. This integrated approach yields unique insight into the experimental sensitivity of RDFs to changes in local geometries, the composition of solvation environments about ions, and the challenge of experimentally differentiating the ensemble of all superimposed local environments-a feature of increasing importance within the extreme condition of high ionic strength.
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Affiliation(s)
- David Semrouni
- Department of Chemistry and the Materials Science and Engineering Program, Washington State University, Pullman, WA 99164, USA.
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19
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Fischer SA, Dunlap BI, Gunlycke D. Correlated dynamics in aqueous proton diffusion. Chem Sci 2018; 9:7126-7132. [PMID: 30310634 PMCID: PMC6137442 DOI: 10.1039/c8sc01253a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Accepted: 07/27/2018] [Indexed: 11/24/2022] Open
Abstract
The aqueous proton displays an anomalously large diffusion coefficient that is up to 7 times that of similarly sized cations. There is general consensus that the proton achieves its high diffusion through the Grotthuss mechanism, whereby protons hop from one molecule to the next. A main assumption concerning the extraction of the timescale of the Grotthuss mechanism from experimental results has been that, on average, there is an equal probability for the proton to hop to any of its neighboring water molecules. Herein, we present ab initio simulations that show this assumption is not generally valid. Specifically, we observe that there is an increased probability for the proton to revert back to its previous location. These correlations indicate that the interpretation of the experimental results need to be re-examined and suggest that the timescale of the Grotthuss mechanism is significantly shorter than was previously thought.
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Affiliation(s)
- Sean A Fischer
- Chemistry Division , U. S. Naval Research Laboratory , Washington , DC 20375 , USA .
| | - Brett I Dunlap
- Chemistry Division , U. S. Naval Research Laboratory , Washington , DC 20375 , USA .
| | - Daniel Gunlycke
- Chemistry Division , U. S. Naval Research Laboratory , Washington , DC 20375 , USA .
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20
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Wildman A, Martinez-Baez E, Fulton J, Schenter G, Pearce C, Clark AE, Li X. Anticorrelated Contributions to Pre-edge Features of Aluminate Near-Edge X-ray Absorption Spectroscopy in Concentrated Electrolytes. J Phys Chem Lett 2018; 9:2444-2449. [PMID: 29672058 DOI: 10.1021/acs.jpclett.8b00642] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Ion pairing within complex solutions and electrolytes is a difficult phenomenon to measure and investigate, yet it has significant impact upon macroscopic processes, such as crystal formation. Traditional methods of detecting and characterizing ion pairing are sensitive to contact ion pairs, may require minimum concentrations that limit applicability, and can have difficulty in characterizing solutions with many components. Because of its element specificity and sensitivity to local environment, X-ray absorption near edge structure (XANES) is a promising tool for investigating ion pairing in complex solutions. In concentrated sodium aluminate solutions, a shift in the pre-edge shoulder correlated to sodium concentration is observed, and the physical origins of that shift are investigated using energy specific time-dependent density functional theory of subensembles obtained from ab initio molecular dynamics. Two transitions are found to contribute to the pre-edge feature, yet they are anticorrelated with respect to the sodium···aluminate distance. Unexpectedly, this causes Al XANES to be an effective probe for longer-range ion interactions than the traditional counterparts of NMR or vibrational spectroscopies. Given the nature of the transitions involved, this observation may be extended to other systems where ion-ion interactions dominate; however, a complete understanding of the contributing transitions is necessary for accurate analysis of XANES pre-edge features in concentrated electrolytes.
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Affiliation(s)
- Andrew Wildman
- Department of Chemistry , University of Washington , Seattle , Washington 98195 , United States
| | - Ernesto Martinez-Baez
- Department of Chemistry , Washington State University , Pullman , Washington 99164 , United States
| | - John Fulton
- Pacific Northwest National Laboratory , Richland , Washington 99354 , United States
| | - Gregory Schenter
- Pacific Northwest National Laboratory , Richland , Washington 99354 , United States
| | - Carolyn Pearce
- Pacific Northwest National Laboratory , Richland , Washington 99354 , United States
| | - Aurora E Clark
- Department of Chemistry , Washington State University , Pullman , Washington 99164 , United States
| | - Xiaosong Li
- Department of Chemistry , University of Washington , Seattle , Washington 98195 , United States
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21
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Sbroscia M, Sodo A, Bruni F, Corridoni T, Ricci MA. OH Stretching Dynamics in Hydroxide Aqueous Solutions. J Phys Chem B 2018. [PMID: 29533618 DOI: 10.1021/acs.jpcb.8b01094] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The concept of ions being either water "structure makers" or water "breakers" seems to be inconsistent with the existence of a critical number of water molecules per ion dictating the properties of an aqueous solution, independent of the ion identity. To investigate this issue, Raman spectra of hydroxide aqueous solutions in the region of the OH stretching mode have been obtained under ambient conditions and at concentrations ranging from extreme dilution to the solubility limit. Spectra have been analyzed with a relatively model-free approach, in terms of a superposition of contributions due to the vibrations of the OH- ions, with two contributions due to the solvent. One of these latter contributions falls at wavenumbers very close to that of the OH- stretching band, sharing with it its concentration dependence of the full width at half maximum (FWHM). The other contribution due to the solvent is very broad, with increasing FWHM with increasing ion concentration. In the light of these observations, an interpretation of the Raman spectra, based on the possibility of distinguishing the self and distinct contributions, is proposed. The present analysis is supported by structural data on the same solutions and puts into evidence relevant structural and dynamical changes occurring when the number of water molecules available per solute is below ∼20, irrespective of the ion identity.
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Affiliation(s)
- Marco Sbroscia
- Dipartimento di Scienze , Universitá degli Studi Roma Tre , Via della Vasca Navale 84 , 00146 Roma , Italy
| | - Armida Sodo
- Dipartimento di Scienze , Universitá degli Studi Roma Tre , Via della Vasca Navale 84 , 00146 Roma , Italy
| | - Fabio Bruni
- Dipartimento di Scienze , Universitá degli Studi Roma Tre , Via della Vasca Navale 84 , 00146 Roma , Italy
| | - Tommaso Corridoni
- Dipartimento di Scienze , Universitá degli Studi Roma Tre , Via della Vasca Navale 84 , 00146 Roma , Italy
| | - Maria Antonietta Ricci
- Dipartimento di Scienze , Universitá degli Studi Roma Tre , Via della Vasca Navale 84 , 00146 Roma , Italy
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22
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Sahle CJ, Niskanen J, Schmidt C, Stefanski J, Gilmore K, Forov Y, Jahn S, Wilke M, Sternemann C. Cation Hydration in Supercritical NaOH and HCl Aqueous Solutions. J Phys Chem B 2017; 121:11383-11389. [DOI: 10.1021/acs.jpcb.7b09688] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christoph J. Sahle
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Johannes Niskanen
- Institute
for Methods and Instrumentation for Synchrotron Radiation Research, Helmholtz Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str.
15, 12489 Berlin, Germany
| | - Christian Schmidt
- Deutsches GeoForschungsZentrum GFZ, Section 4.3, Telegrafenberg, 14473 Potsdam, Germany
| | - Johannes Stefanski
- Institute
of Geology and Mineralogy, University of Cologne, Zülpicher
Strasse 49b, 50674 Köln, Germany
| | - Keith Gilmore
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Yury Forov
- Fakultät
Physik/DELTA, Technische Universität Dortmund, 44221 Dortmund, Germany
| | - Sandro Jahn
- Institute
of Geology and Mineralogy, University of Cologne, Zülpicher
Strasse 49b, 50674 Köln, Germany
| | - Max Wilke
- Institute
of Earth and Environmental Science-Earth Science, Universität Potsdam, 14476 Potsdam, Germany
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23
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Abstract
An important limitation of standard classical molecular dynamics simulations is the inability to make or break chemical bonds. This restricts severely our ability to study processes that involve even the simplest of chemical reactions, the transfer of a proton. Existing approaches for allowing proton transfer in the context of classical mechanics are rather cumbersome and have not achieved widespread use and routine status. Here we reconsider the combination of molecular dynamics with periodic stochastic proton hops. To ensure computational efficiency, we propose a non-Boltzmann acceptance criterion that is heuristically adjusted to maintain the correct or desirable thermodynamic equilibria between different protonation states and proton transfer rates. Parameters are proposed for hydronium, Asp, Glu, and His. The algorithm is implemented in the program CHARMM and tested on proton diffusion in bulk water and carbon nanotubes and on proton conductance in the gramicidin A channel. Using hopping parameters determined from proton diffusion in bulk water, the model reproduces the enhanced proton diffusivity in carbon nanotubes and gives a reasonable estimate of the proton conductance in gramicidin A.
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Affiliation(s)
- Themis Lazaridis
- Department of Chemistry, City College of New York/CUNY , 160 Convent Avenue, New York, New York 10031, United States.,Graduate Programs in Chemistry, Biochemistry & Physics, Graduate Center, City University of New York , 365 Fifth Ave, New York, New York 10016, United States
| | - Gerhard Hummer
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics , Max-von-Laue Strasse 3, 60438 Frankfurt am Main, Germany
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24
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Daly CA, Streacker LM, Sun Y, Pattenaude SR, Hassanali AA, Petersen PB, Corcelli SA, Ben-Amotz D. Decomposition of the Experimental Raman and Infrared Spectra of Acidic Water into Proton, Special Pair, and Counterion Contributions. J Phys Chem Lett 2017; 8:5246-5252. [PMID: 28976760 DOI: 10.1021/acs.jpclett.7b02435] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Textbooks describe excess protons in liquid water as hydronium (H3O+) ions, although their true structure remains lively debated. To address this question, we have combined Raman and infrared (IR) multivariate curve resolution spectroscopy with ab initio molecular dynamics and anharmonic vibrational spectroscopic calculations. Our results are used to resolve, for the first time, the vibrational spectra of hydrated protons and counterions and reveal that there is little ion-pairing below 2 M. Moreover, we find that isolated excess protons are strongly IR active and nearly Raman inactive (with vibrational frequencies of ∼1500 ± 500 cm-1), while flanking water OH vibrations are both IR and Raman active (with higher frequencies of ∼2500 ± 500 cm-1). The emerging picture is consistent with Georg Zundel's seminal work, as well as recent ultrafast dynamics studies, leading to the conclusion that protons in liquid water are primarily hydrated by two flanking water molecules, with a broad range of proton hydrogen bond lengths and asymmetries.
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Affiliation(s)
- Clyde A Daly
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Louis M Streacker
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Yuchen Sun
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Shannon R Pattenaude
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Ali A Hassanali
- Condensed Matter and Statistical Physics, International Centre for Theoretical Physics , Strada Costiera, 11, I-34151 Trieste, Italy
| | - Poul B Petersen
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Steven A Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Dor Ben-Amotz
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
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25
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Prototropism and dynamics of an anticancer drug in reverse micelles: Focus on the variation of pH in reverse micelles having w0≥ 10. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.08.076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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26
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Zhang W, van Duin ACT. Second-Generation ReaxFF Water Force Field: Improvements in the Description of Water Density and OH-Anion Diffusion. J Phys Chem B 2017; 121:6021-6032. [DOI: 10.1021/acs.jpcb.7b02548] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Weiwei Zhang
- Department of Mechanical
and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Adri C. T. van Duin
- Department of Mechanical
and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
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27
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White AD, Knight C, Hocky GM, Voth GA. Communication: Improved ab initio molecular dynamics by minimally biasing with experimental data. J Chem Phys 2017; 146:041102. [DOI: 10.1063/1.4974837] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Andrew D. White
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 S Ellis Ave., Chicago, Illinois 60637, USA
- Department of Chemical Engineering, University of Rochester, Rochester, New York 14627, USA
| | - Chris Knight
- Leadership Computing Facility, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA
| | - Glen M. Hocky
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 S Ellis Ave., Chicago, Illinois 60637, USA
| | - Gregory A. Voth
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 S Ellis Ave., Chicago, Illinois 60637, USA
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28
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Martí J. Potentials of mean force in acidic proton transfer reactions in constrained geometries. MOLECULAR SIMULATION 2016. [DOI: 10.1080/08927022.2016.1239824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, Barcelona, Spain
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29
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Tahat A, Martí J. Multistate empirical valence bond study of temperature and confinement effects on proton transfer in water inside hydrophobic nanochannels. J Comput Chem 2016; 37:1935-46. [PMID: 27189810 DOI: 10.1002/jcc.24411] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 04/12/2016] [Accepted: 05/02/2016] [Indexed: 01/08/2023]
Abstract
Microscopic characteristics of an aqueous excess proton in a wide range of thermodynamic states, from low density amorphous ices (down to 100 K) to high temperature liquids under the critical point (up to 600 K), placed inside hydrophobic graphene slabs at the nanometric scale (with interplate distances between 3.1 and 0.7 nm wide) have been analyzed by means of molecular dynamics simulations. Water-proton and carbon-proton forces were modeled with a multistate empirical valence bond method. Densities between 0.07 and 0.02 Å(-3) have been considered. As a general trend, we observed a competition between effects of confinement and temperature on structure and dynamical properties of the lone proton. Confinement has strong influence on the local structure of the proton, whereas the main effect of temperature on proton properties is observed on its dynamics, with significant variation of proton transfer rates, proton diffusion coefficients, and characteristic frequencies of vibrational motions. Proton transfer is an activated process with energy barriers between 1 and 10 kJ/mol for both proton transfer and diffusion, depending of the temperature range considered and also on the interplate distance. Arrhenius-like behavior of the transfer rates and of proton diffusion are clearly observed for states above 100 K. Spectral densities of proton species indicated that in all states Zundel-like and Eigen-like complexes survive at some extent. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Amani Tahat
- Department of Physics, Technical University of Catalonia-Barcelona Tech, B4-B5 Northern Campus UPC. Jordi Girona, 1-3, Barcelona, Catalonia, 08034, Spain
| | - Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, B4-B5 Northern Campus UPC. Jordi Girona, 1-3, Barcelona, Catalonia, 08034, Spain
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30
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Humphreys EK, Allan PK, Welbourn RJL, Youngs TGA, Soper AK, Grey CP, Clarke SM. A Neutron Diffraction Study of the Electrochemical Double Layer Capacitor Electrolyte Tetrapropylammonium Bromide in Acetonitrile. J Phys Chem B 2015; 119:15320-33. [DOI: 10.1021/acs.jpcb.5b08248] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elizabeth K. Humphreys
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Phoebe K. Allan
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- Gonville and Caius College, Trinity
Street, Cambridge CB2 1TA, United Kingdom
| | - Rebecca J. L. Welbourn
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- BP Institute, University of Cambridge, Madingley Road, Cambridge CB3 0EZ, United Kingdom
| | - Tristan G. A. Youngs
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX, United Kingdom
| | - Alan K. Soper
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX, United Kingdom
| | - Clare P. Grey
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Stuart M. Clarke
- Department
of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- BP Institute, University of Cambridge, Madingley Road, Cambridge CB3 0EZ, United Kingdom
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31
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Biswas R, Tse YLS, Tokmakoff A, Voth GA. Role of Presolvation and Anharmonicity in Aqueous Phase Hydrated Proton Solvation and Transport. J Phys Chem B 2015; 120:1793-804. [PMID: 26575795 DOI: 10.1021/acs.jpcb.5b09466] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Results from condensed phase ab initio molecular dynamics (AIMD) simulations suggest a proton transfer reaction is facilitated by "presolvation" in which the hydronium is transiently solvated by four water molecules, similar to the typical solvation structure of water, by accepting a weak hydrogen bond from the fourth water molecule. A new version 3.2 multistate empirical valence bond (MS-EVB 3.2) model for the hydrated excess proton incorporating this presolvation behavior is therefore developed. The classical MS-EVB simulations show similar structural properties as those of the previous model but with significantly improved diffusive behavior. The inclusion of nuclear quantum effects in the MS-EVB also provides an even better description of the proton diffusion rate. To quantify the influence of anharmonicity, a second model (aMS-EVB 3.2) is developed using the anharmonic aSPC/Fw water model, which provides similar structural properties but improved spectroscopic responses at high frequencies.
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Affiliation(s)
- Rajib Biswas
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago , Chicago, Illinois 60637, United States
| | - Ying-Lung Steve Tse
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago , Chicago, Illinois 60637, United States
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago , Chicago, Illinois 60637, United States
| | - Gregory A Voth
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago , Chicago, Illinois 60637, United States
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32
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Tse YLS, Chen C, Lindberg GE, Kumar R, Voth GA. Propensity of Hydrated Excess Protons and Hydroxide Anions for the Air-Water Interface. J Am Chem Soc 2015; 137:12610-6. [PMID: 26366480 DOI: 10.1021/jacs.5b07232] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Significant effort has been undertaken to better understand the molecular details governing the propensity of ions for the air-water interface. Facilitated by computationally efficient reactive molecular dynamics simulations, new and statistically conclusive molecular-scale results on the affinity of the hydrated excess proton and hydroxide anion for the air-water interface are presented. These simulations capture the dynamic bond breaking and formation processes (charge defect delocalization) that are important for correctly describing the solvation and transport of these complex species. The excess proton is found to be attracted to the interface, which is correlated with a favorable enthalpic contribution and consistent with reducing the disruption in the hydrogen bond network caused by the ion complex. However, a recent refinement of the underlying reactive potential energy function for the hydrated excess proton shows the interfacial attraction to be weaker, albeit nonzero, a result that is consistent with the experimental surface tension measurements. The influence of a weak hydrogen bond donated from water to the protonated oxygen, recently found to play an important role in excess hydrated proton transport in bulk water, is seen to also be important for this study. In contrast, the hydroxide ion is found to be repelled from the air-water interface. This repulsion is characterized by a reduction of the energetically favorable ion-water interactions, which creates an enthalpic penalty as the ion approaches the interface. Finally, we find that the fluctuation in the coordination number around water sheds new light on the observed entropic trends for both ions.
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Affiliation(s)
- Ying-Lung Steve Tse
- Department of Chemistry, James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States
| | - Chen Chen
- Department of Chemistry, James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States.,College of Chemistry and Molecular Sciences, Hubei Key Lab of Electrochemical Power Sources, Wuhan University , Wuhan 430072, China
| | - Gerrick E Lindberg
- Department of Chemistry and Biochemistry, Northern Arizona University , Flagstaff, Arizona 86011, United States
| | - Revati Kumar
- Department of Chemistry, Louisiana State University , Baton Rouge, Louisiana 70803, United States
| | - Gregory A Voth
- Department of Chemistry, James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States
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33
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Tahat A, Martí J. Proton transfer in liquid water confined inside graphene slabs. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:032402. [PMID: 26465477 DOI: 10.1103/physreve.92.032402] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Indexed: 06/05/2023]
Abstract
The microscopic structure and dynamics of an excess proton in water constrained in narrow graphene slabs between 0.7 and 3.1 nm wide has been studied by means of a series of molecular dynamics simulations. Interaction of water and carbon with the proton species was modeled using a multistate empirical valence bond Hamiltonian model. The analysis of the effects of confinement on proton solvation structure and on its dynamical properties has been considered for varying densities. The system is organized in one interfacial and a bulk-like region, both of variable size. In the widest interplate separations, the lone proton shows a marked tendency to place itself in the bulk phase of the system, due to the repulsive interaction with the carbon atoms. However, as the system is compressed and the proton is forced to move to the vicinity of graphene walls it moves closer to the interface, producing a neat enhancement of the local structure. We found a marked slowdown of proton transfer when the separation of the two graphene plates is reduced. In the case of lowest distances between graphene plates (0.7 and 0.9 nm), only one or two water layers persist and the two-dimensional character of water structure becomes evident. By means of spectroscopical analysis, we observed the persistence of Zundel and Eigen structures in all cases, although at low interplate separations a signature frequency band around 2500 cm^{-1} suffers a blue shift and moves to characteristic values of asymmetric hydronium ion vibrations, indicating some unstability of the typical Zundel-Eigen moieties and their eventual conversion to a single hydronium species solvated by water.
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Affiliation(s)
- Amani Tahat
- Department of Physics and Nuclear Engineering, Technical University of Catalonia-Barcelona Tech, Building B5, Northern Campus UPC. Jordi Girona, 1-3, 08034 Barcelona, Catalonia, Spain
| | - Jordi Martí
- Department of Physics and Nuclear Engineering, Technical University of Catalonia-Barcelona Tech, Building B5, Northern Campus UPC. Jordi Girona, 1-3, 08034 Barcelona, Catalonia, Spain
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34
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Mabuchi T, Fukushima A, Tokumasu T. A modified two-state empirical valence bond model for proton transport in aqueous solutions. J Chem Phys 2015; 143:014501. [DOI: 10.1063/1.4926394] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Takuya Mabuchi
- Graduate School of Engineering, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Akinori Fukushima
- Institute of Fluid Science, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Takashi Tokumasu
- Institute of Fluid Science, Tohoku University, Sendai, Miyagi 980-8577, Japan
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35
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Bankura A, Santra B, DiStasio RA, Swartz CW, Klein ML, Wu X. A systematic study of chloride ion solvation in water using van der Waals inclusive hybrid density functional theory. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1059959] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Arindam Bankura
- Institute for Computational Molecular Science and Department of Chemistry, Temple University , Philadelphia, PA, USA
| | - Biswajit Santra
- Department of Chemistry, Princeton University , Princeton, NJ, USA
| | | | - Charles W. Swartz
- Institute for Computational Molecular Science and Department of Chemistry, Temple University , Philadelphia, PA, USA
| | - Michael L. Klein
- Institute for Computational Molecular Science and Department of Chemistry, Temple University , Philadelphia, PA, USA
| | - Xifan Wu
- Department of Physics, Temple University , Philadelphia, PA, USA
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36
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Tse YLS, Knight C, Voth GA. An analysis of hydrated proton diffusion in ab initio molecular dynamics. J Chem Phys 2015; 142:014104. [DOI: 10.1063/1.4905077] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ying-Lung Steve Tse
- Department of Chemistry, James Franck Institute, and Computation Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - Chris Knight
- Leadership Computing Facility, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Gregory A. Voth
- Department of Chemistry, James Franck Institute, and Computation Institute, University of Chicago, Chicago, Illinois 60637, USA
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37
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Goyal P, Qian HJ, Irle S, Lu X, Roston D, Mori T, Elstner M, Cui Q. Molecular simulation of water and hydration effects in different environments: challenges and developments for DFTB based models. J Phys Chem B 2014; 118:11007-27. [PMID: 25166899 PMCID: PMC4174991 DOI: 10.1021/jp503372v] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We discuss the description of water and hydration effects that employs an approximate density functional theory, DFTB3, in either a full QM or QM/MM framework. The goal is to explore, with the current formulation of DFTB3, the performance of this method for treating water in different chemical environments, the magnitude and nature of changes required to improve its performance, and factors that dictate its applicability to reactions in the condensed phase in a QM/MM framework. A relatively minor change (on the scale of kBT) in the O-H repulsive potential is observed to substantially improve the structural properties of bulk water under ambient conditions; modest improvements are also seen in dynamic properties of bulk water. This simple change also improves the description of protonated water clusters, a solvated proton, and to a more limited degree, a solvated hydroxide. By comparing results from DFTB3 models that differ in the description of water, we confirm that proton transfer energetics are adequately described by the standard DFTB3/3OB model for meaningful mechanistic analyses. For QM/MM applications, a robust parametrization of QM-MM interactions requires an explicit consideration of condensed phase properties, for which an efficient sampling technique was developed recently and is reviewed here. The discussions help make clear the value and limitations of DFTB3 based simulations, as well as the developments needed to further improve the accuracy and transferability of the methodology.
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Affiliation(s)
- Puja Goyal
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States
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39
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Yepes D, Seidel R, Winter B, Blumberger J, Jaque P. Photoemission Spectra and Density Functional Theory Calculations of 3d Transition Metal–Aqua Complexes (Ti–Cu) in Aqueous Solution. J Phys Chem B 2014; 118:6850-63. [DOI: 10.1021/jp5012389] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Diana Yepes
- Departamento
de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Avenida Republica 275, Santiago 8370146, Chile
| | - Robert Seidel
- Department
of Chemistry, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089, United States
| | - Bernd Winter
- Joint
Laboratory for Ultrafast Dynamics in Solutions and at Interfaces (JULiq), Helmholtz−Zentrum Berlin für Materialien und Energie, and BESSY II, Albert−Einstein−Strasse 15, D-12489 Berlin, Germany
| | - Jochen Blumberger
- Department
of Physics and Astronomy, University College London, London WC1E6BT, United Kingdom
| | - Pablo Jaque
- Departamento
de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Avenida Republica 275, Santiago 8370146, Chile
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40
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Baer MD, Fulton JL, Balasubramanian M, Schenter GK, Mundy CJ. Persistent Ion Pairing in Aqueous Hydrochloric Acid. J Phys Chem B 2014; 118:7211-20. [DOI: 10.1021/jp501091h] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Marcel D. Baer
- Physical
Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - John L. Fulton
- Physical
Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | | | - Gregory K. Schenter
- Physical
Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Christopher J. Mundy
- Physical
Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
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41
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Tahat A, Martí J. Dynamical aspects of intermolecular proton transfer in liquid water and low-density amorphous ices. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:052130. [PMID: 25353762 DOI: 10.1103/physreve.89.052130] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Indexed: 06/04/2023]
Abstract
The microscopic dynamics of an excess proton in water and in low-density amorphous ices has been studied by means of a series of molecular dynamics simulations. Interaction of water with the proton species was modelled using a multistate empirical valence bond Hamiltonian model. The analysis of the effects of low temperatures on proton diffusion and transfer rates has been considered for a temperature range between 100 and 298 K at the constant density of 1 g cm(-3). We observed a marked slowdown of proton transfer rates at low temperatures, but some episodes are still seen at 100 K. In a similar fashion, mobility of the lone proton gets significantly reduced when temperature decreases below 273 K. The proton transfer in low-density amorphous ice is an activated process with energy barriers between 1-10 kJ/mol depending of the temperature range considered and eventually showing Arrhenius-like behavior. Spectroscopic data indicated the survival of both Zundel and Eigen structures along the whole temperature range, revealed by significant spectral frequency shifts.
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Affiliation(s)
- Amani Tahat
- Department of Physics and Nuclear Engineering, Technical University of Catalonia-Barcelona Tech, Building B5, Northern Campus UPC. Jordi Girona, 1-3, 08034 Barcelona, Catalonia, Spain
| | - Jordi Martí
- Department of Physics and Nuclear Engineering, Technical University of Catalonia-Barcelona Tech, Building B5, Northern Campus UPC. Jordi Girona, 1-3, 08034 Barcelona, Catalonia, Spain
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42
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Wolf MG, Groenhof G. Explicit proton transfer in classical molecular dynamics simulations. J Comput Chem 2014; 35:657-71. [DOI: 10.1002/jcc.23536] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 12/13/2013] [Accepted: 12/18/2013] [Indexed: 12/25/2022]
Affiliation(s)
- Maarten G. Wolf
- Computational Biomolecular Chemistry, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11; Göttingen D-37077, Germany
| | - Gerrit Groenhof
- Computational Biomolecular Chemistry, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11; Göttingen D-37077, Germany
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43
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Chen C, Huang C, Waluyo I, Nordlund D, Weng TC, Sokaras D, Weiss T, Bergmann U, Pettersson LGM, Nilsson A. Solvation structures of protons and hydroxide ions in water. J Chem Phys 2013; 138:154506. [PMID: 23614429 DOI: 10.1063/1.4801512] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
X-ray Raman spectroscopy (XRS) combined with small-angle x-ray scattering (SAXS) were used to study aqueous solutions of HCl and NaOH. Hydrated structures of H(+) and OH(-) are not simple mirror images of each other. While both ions have been shown to strengthen local hydrogen bonds in the hydration shell as indicated by XRS, SAXS suggests that H(+) and OH(-) have qualitatively different long-range effects. The SAXS structure factor of HCl (aq) closely resembles that of pure water, while NaOH (aq) behaves similar to NaF (aq). We propose that protons only locally enhance hydrogen bonds while hydroxide ions induce tetrahedrality in the overall hydrogen bond network of water.
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Affiliation(s)
- Chen Chen
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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44
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Structure and thermodynamics of H3O+(H2O)8 clusters: A combined molecular dynamics and quantum mechanics approach. COMPUT THEOR CHEM 2013. [DOI: 10.1016/j.comptc.2013.07.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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45
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A computational study of the suppression of ammonia volatility in aqueous systems using ionic additives. Struct Chem 2013. [DOI: 10.1007/s11224-013-0263-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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46
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Lockwood GK, Garofalini SH. Lifetimes of excess protons in water using a dissociative water potential. J Phys Chem B 2013; 117:4089-97. [PMID: 23565831 DOI: 10.1021/jp310300x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Molecular dynamics simulations using a dissociative water potential were applied to study transport of excess protons in water and determine the applicability of this potential to describe such behavior. While originally developed for gas-phase molecules and bulk liquid water, the potential is transferrable to nanoconfinement and interface scenarios. Applied here, it shows proton behavior consistent with ab initio calculations and empirical models specifically designed to describe proton transport. Both Eigen and Zundel complexes are observed in the simulations showing the Eigen-Zundel-Eigen-type mechanism. In addition to reproducing the short-time rattling of the excess proton between the two oxygens of Zundel complexes, a picosecond-scale lifetime was also found. These longer-lived H3O(+) ions are caused by the rapid conversion of the local solvation structure around the transferring proton from a Zundel-like form to an Eigen-like form following the transfer, effectively severing the path along which the proton can rattle. The migration of H(+) over long times (>100 ps) deviates from the conventional short-time multiexponentially decaying lifetime autocorrelation model and follows the t(-3/2) power-law behavior. The potential function employed here matches many of the features of proton transport observed in ab initio molecular dynamics simulations as well as the highly developed empirical valence bond models, yet is computationally very efficient, enabling longer time and larger systems to be studied.
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Affiliation(s)
- Glenn K Lockwood
- Interfacial Molecular Science Laboratory, Department of Materials Science and Engineering, Rutgers University, 607 Taylor Rd., Piscataway, New Jersey 08855, USA
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47
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Casella AJ, Levitskaia TG, Peterson JM, Bryan SA. Water O–H Stretching Raman Signature for Strong Acid Monitoring via Multivariate Analysis. Anal Chem 2013; 85:4120-8. [DOI: 10.1021/ac4001628] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Amanda J. Casella
- Energy and
Environment Directorate, Pacific Northwest
National Laboratory, Richland, Washington 99352, United States
| | - Tatiana G. Levitskaia
- Energy and
Environment Directorate, Pacific Northwest
National Laboratory, Richland, Washington 99352, United States
| | - James M. Peterson
- Energy and
Environment Directorate, Pacific Northwest
National Laboratory, Richland, Washington 99352, United States
| | - Samuel A. Bryan
- Energy and
Environment Directorate, Pacific Northwest
National Laboratory, Richland, Washington 99352, United States
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48
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Shevkunov SV. Computer simulation of dissociative equilibrium in aqueous NaCl electrolyte with account for polarization and ion recharging. Ionization mechanism. RUSS J ELECTROCHEM+ 2013. [DOI: 10.1134/s1023193513030130] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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49
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Ge L, Bernasconi L, Hunt P. Linking electronic and molecular structure: insight into aqueous chloride solvation. Phys Chem Chem Phys 2013; 15:13169-83. [DOI: 10.1039/c3cp50652e] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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50
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McGrath MJ, Kuo IFW, Ngouana W. BF, Ghogomu JN, Mundy CJ, Marenich AV, Cramer CJ, Truhlar DG, Siepmann JI. Calculation of the Gibbs free energy of solvation and dissociation of HCl in water via Monte Carlo simulations and continuum solvation models. Phys Chem Chem Phys 2013; 15:13578-85. [DOI: 10.1039/c3cp51762d] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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