1
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Benjamin I. Hydronium Ion Transport across the Liquid/Liquid Interface Assisted by a Phase-Transfer Catalyst: Structure and Thermodynamics Using Molecular Dynamics Simulation. J Phys Chem B 2024; 128:9613-9618. [PMID: 39302249 DOI: 10.1021/acs.jpcb.4c04983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2024]
Abstract
Molecular dynamics simulations are used to examine the thermodynamic and structural aspects of the transfer of the classical hydronium ion (H3O+) across a water/1,2-dichloroethane (DCE) interface assisted by the phase-transfer catalyst (PTC) tetrakis(pentafluorophenyl) borate anion (TPFB-). The free energy of transfer from water to DCE of the H3O+-TPFB- ion pair is calculated to be 6 ± 1 kcal/mol, significantly less than that of the free hydronium ion (17 ± 1 kcal/mol). The ion pair is relatively stable at the interface and in the organic phase when it is accompanied by three water molecules with a small barrier to dissociation that supports its utility as a PTC. An examination of the hydration structure that accompanies the transfer of the ion pair shows that the ion pair, like the free hydronium ion, is transferred with the assistance of a finger-like water structure.
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Affiliation(s)
- Ilan Benjamin
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
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2
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Zhang P, Feng M, Xu X. Double-Layer Distribution of Hydronium and Hydroxide Ions in the Air-Water Interface. ACS PHYSICAL CHEMISTRY AU 2024; 4:336-346. [PMID: 39069983 PMCID: PMC11274287 DOI: 10.1021/acsphyschemau.3c00076] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 07/30/2024]
Abstract
The acid-base nature of the aqueous interface has long been controversial. Most macroscopic experiments suggest that the air-water interface is basic based on the detection of negative charges at the interface that indicates the enrichment of hydroxides (OH-), whereas microscopic studies mostly support the acidic air-water interface with the observation of hydronium (H3O+) accumulation in the top layer of the interface. It is crucial to clarify the interfacial preference of OH- and H3O+ ions for rationalizing the debate. In this work, we perform deep potential molecular dynamics simulations to investigate the preferential distribution of OH- and H3O+ ions at the aqueous interfaces. The neural network potential energy surface is trained based on density functional theory calculations with the SCAN functional, which can accurately describe the diffusion of these two ions both in the interface and in the bulk water. In contrast to the previously reported single ion enrichment, we show that both OH- and H3O+ surprisingly prefer to accumulate in interfaces but at different interfacial depths, rendering a double-layer ionic distribution within ∼1 nm near the Gibbs dividing surface. The H3O+ preferentially resides in the topmost layer of the interface, but the OH-, which is enriched in the deeper interfacial layer, has a higher equilibrium concentration due to the more negative free energy of interfacial stabilization [-0.90 (OH-) vs -0.56 (H3O+) kcal/mol]. The present finding of the ionic double-layer distribution may qualitatively offer a self-consistent explanation for the long-term controversy about the acid-base nature of the air-water interface.
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Affiliation(s)
- Pengchao Zhang
- Center
for Combustion Energy, Department of Energy and Power Engineering,
and Key Laboratory for Thermal Science and Power Engineering of Ministry
of Education, Tsinghua University, Beijing 100084, China
| | - Muye Feng
- School
of Mechanical and Power Engineering, Nanjing
Tech University, Nanjing 211816, China
| | - Xuefei Xu
- Center
for Combustion Energy, Department of Energy and Power Engineering,
and Key Laboratory for Thermal Science and Power Engineering of Ministry
of Education, Tsinghua University, Beijing 100084, China
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3
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Rashid MAM, Rahman M, Acter T, Uddin N. Identifying the acidic or basic behavior of surface water: a QM/MM-MD study. Phys Chem Chem Phys 2023; 25:31194-31205. [PMID: 37955174 DOI: 10.1039/d3cp02080k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
Controversies on the water surface were theoretically addressed with the help of large scale quantum mechanical molecular dynamics (QMMD) simulations on water surface model systems with and without excess hydroniums and hydroxides. It was revealed that the thermodynamic surface structures of these ions strongly depend on their location and dipole orientation. Fast hydronium diffusion by proton transfer establishes a wider kinetic depth distribution (∼6 Å) than that predicted by its thermodynamic affinity for the water surface, while slow hydroxide is shallowly trapped below the outermost molecular layer (3-4 Å). In addition, the anisotropic orientation of surface water dipole can generate a substantial magnitude of surface potential, which extends to a depth of a few molecular layers. With these distinctively different surface properties of two ions and water molecules, the seemingly contradictory observations of acidic and negatively charged water surfaces may be successfully explained. That is, the negative surface charge of neutral water mostly stems from intrinsic water properties such as water dipole orientation and electron density spillage at the surface, rather than surface OH- ions. The enhanced acidity of the water surface can be attributed in large part to the kinetic depth profile of ion density in addition to static thermodynamic origin. Furthermore, the different depth profiles of the two ions may differently affect the surface-sensitive spectroscopic observations.
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Affiliation(s)
- Md Al Mamunur Rashid
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul, 02792, South Korea
| | - Mofizur Rahman
- Research and Development Center, Berger Paints Bangladesh Limited, Berger House, Dhaka-1230, Bangladesh
| | - Thamina Acter
- Department of Mathematical and Physical Sciences, East West University, Aftabnagar, Dhaka-1212, Bangladesh
| | - Nizam Uddin
- Department of Nutrition and Food Engineering, Daffodil International University, Birulia, Dhaka-1216, Bangladesh.
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4
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Bandyopadhyay D, Bhanja K, Choudhury N. On the Propensity of Excess Hydroxide Ions at the Alcohol Monolayer-Water Interface. J Phys Chem B 2023; 127:783-793. [PMID: 36639623 DOI: 10.1021/acs.jpcb.2c05719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Atomistic molecular dynamics simulations have been employed to study the self-ion (H+ and OH-) distribution at the interface between long-chain C16-OH alcohol (cetyl alcohol) monolayer and water. It is well known that the free air-water interface is acidic due to accumulation of the hydronium (H3O+) ions at the interface. In the present study, we have observed that contrary to the air-water interface, at the long-chain alcohol monolayer-water interface, it is the hydroxide (OH-) ion, not the hydronium ion (H3O+) that gets accumulated. By calculating the potential of mean forces, it is confirmed that there is extra stabilization for the OH- ions at the interface relative to the bulk, but no such stabilization is observed for the H3O+ ions. By analyzing the interaction of the self-ions with other constituents in the medium, it is clearly shown that the favorable interaction of the OH- ions with the alcoholic -OH groups stabilizes this ion at the interface. By calculating coordination numbers of the self-ions it is observed that around 50% water neighbors are substituted by alcoholic -OH in case of the hydroxide ion at the interface, whereas in the case of hydronium ions, only 15% water neighbors are substituted by the alcoholic -OH. The most interesting observation about the local structure and H-bonding pattern is that the hydroxide ion acts solely as the H-bond acceptor, but the hydronium ion acts only as the H-bond donor.
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Affiliation(s)
| | - Kalyan Bhanja
- Heavy Water Division, Bhabha Atomic Research Centre, Mumbai400 085, India
| | - Niharendu Choudhury
- Theoretical Chemistry Section, Chemistry Division, Bhabha Atomic Research Centre, Mumbai400 085, India.,Homi Bhabha National Institute, Anushaktinagar, Mumbai400 094, India
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5
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Lazaridis T. Molecular origins of asymmetric proton conduction in the influenza M2 channel. Biophys J 2023; 122:90-98. [PMID: 36403086 PMCID: PMC9822799 DOI: 10.1016/j.bpj.2022.11.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/13/2022] [Accepted: 11/17/2022] [Indexed: 11/20/2022] Open
Abstract
The M2 proton channel of influenza A is embedded into the viral envelope and allows acidification of the virion when the external pH is lowered. In contrast, no outward proton conductance is observed when the internal pH is lowered, although outward current is observed at positive voltage. Residues Trp41 and Asp44 are known to play a role in preventing pH-driven outward conductance, but the mechanism for this is unclear. We investigate this issue using classical molecular dynamics simulations with periodic proton hops. When all key His37 residues are neutral, inward proton movement is much more facile than outward movement if the His are allowed to shuttle the proton. The preference for inward movement increases further as the charge on the His37 increases. Analysis of the trajectories reveals three factors accounting for this asymmetry. First, in the outward direction, Asp44 traps the hydronium by strong electrostatic interactions. Secondly, Asp44 and Trp41 orient the hydronium with the protons pointing inward, hampering outward Grotthus hopping. As a result, the effective barrier is lower in the inward direction. Trp41 adds to the barrier by weakly H-bonding to potential H+ acceptors. Finally, for charged His, the H3O+ in the inner vestibule tends to get trapped at lipid-lined fenestrations of the cone-shaped channel. Simulations qualitatively reproduce the experimentally observed higher outward conductance of mutants. The ability of positive voltage, unlike proton gradient, to induce an outward current appears to arise from its ability to bias H3O+ and the waters around it toward more H-outward orientations.
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Affiliation(s)
- Themis Lazaridis
- Department of Chemistry, City College of New York/CUNY, New York, New York; Graduate Programs in Chemistry, Biochemistry, and Physics, The Graduate Center, City University of New York, New York, New York.
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6
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Silverstein TP. A critique of the capacitor-based "Transmembrane Electrostatically Localized Proton" hypothesis. J Bioenerg Biomembr 2022; 54:59-65. [PMID: 35190945 DOI: 10.1007/s10863-022-09931-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/26/2022] [Indexed: 11/27/2022]
Abstract
In his Transmembrane Electrostatically Localized Proton hypothesis (TELP), James W. Lee has modeled the bioenergetic membrane as a simple capacitor. According to this model, the surface concentration of protons is completely independent of proton concentration in the bulk phase, and is linearly proportional to the transmembrane potential. Such a proportionality runs counter to the results of experimental measurements, molecular dynamics simulations, and electrostatics calculations. We show that the TELP model dramatically overestimates the surface concentration of protons, and we discuss the electrostatic reasons why a simple capacitor is not an appropriate model for the bioenergetic membrane.
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7
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Silverstein TP. The Proton in Biochemistry: Impacts on Bioenergetics, Biophysical Chemistry, and Bioorganic Chemistry. Front Mol Biosci 2021; 8:764099. [PMID: 34901158 PMCID: PMC8661011 DOI: 10.3389/fmolb.2021.764099] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/11/2021] [Indexed: 11/13/2022] Open
Abstract
The proton is the smallest atomic particle, and in aqueous solution it is the smallest hydrated ion, having only two waters in its first hydration shell. In this article we survey key aspects of the proton in chemistry and biochemistry, starting with the definitions of pH and pK a and their application inside biological cells. This includes an exploration of pH in nanoscale spaces, distinguishing between bulk and interfacial phases. We survey the Eigen and Zundel models of the structure of the hydrated proton, and how these can be used to explain: a) the behavior of protons at the water-hydrophobic interface, and b) the extraordinarily high mobility of protons in bulk water via Grotthuss hopping, and inside proteins via proton wires. Lastly, we survey key aspects of the effect of proton concentration and proton transfer on biochemical reactions including ligand binding and enzyme catalysis, as well as pH effects on biochemical thermodynamics, including the Chemiosmotic Theory. We find, for example, that the spontaneity of ATP hydrolysis at pH ≥ 7 is not due to any inherent property of ATP (or ADP or phosphate), but rather to the low concentration of H+. Additionally, we show that acidification due to fermentation does not derive from the organic acid waste products, but rather from the proton produced by ATP hydrolysis.
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Affiliation(s)
- Todd P Silverstein
- Chemistry Department (emeritus), Willamette University, Salem, OR, United States
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8
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Kronberg R, Laasonen K. Dynamics and Surface Propensity of H + and OH - within Rigid Interfacial Water: Implications for Electrocatalysis. J Phys Chem Lett 2021; 12:10128-10134. [PMID: 34636561 PMCID: PMC8543677 DOI: 10.1021/acs.jpclett.1c02493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/29/2021] [Indexed: 06/13/2023]
Abstract
Facile solvent reorganization promoting ion transfer across the solid-liquid interface is considered a prerequisite for efficient electrocatalysis. We provide first-principles insight into this notion by examining water self-ion dynamics at a highly rigid NaCl(100)-water interface. Through extensive density functional theory molecular dynamics simulations, we demonstrate for both acidic and alkaline solutions that Grotthuss dynamics is not impeded by a rigid water structure. Conversely, decreased proton transfer barriers and a striking propensity of H3O+ and OH- for stationary interfacial water are found. Differences in the ideal hydration structure of the ions, however, distinguish their behavior at the water contact layer. While hydronium can maintain its optimal solvation, the preferentially hypercoordinated hydroxide is repelled from the immediate vicinity of the surface due to interfacial coordination reduction. This has implications for alkaline hydrogen electrosorption in which the formation of undercoordinated OH- at the surface is proposed to contribute to the observed sluggish kinetics.
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9
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Benjamin I. Molecular Dynamics Studies on the Effect of Surface Roughness and Surface Tension on the Thermodynamics and Dynamics of Hydronium Ion Transfer Across the Liquid/Liquid Interface. J Phys Chem B 2020; 124:8711-8718. [PMID: 32902279 DOI: 10.1021/acs.jpcb.0c06304] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Molecular dynamics simulations are used to examine the effect of surface roughness and surface tension on the transfer of the classical hydronium ion (H3O+) across the water/1,2-dichloroethane interface. Free energy of transfer, hydration structure, and dynamics as a function of the ion location along the interface normal are calculated with six different values of a control parameter whose variation modifies the surface tension without impacting the bulk properties of the two solvents. Transfer of the classical hydronium ion across the water/1,2-dichloroethan interface involves the cotransfer of three hydration shell water molecules, independent of the surface tension. However, as the interaction between the two liquids weakens, a rise in interfacial tension and decrease in intrinsic water fingering and capillary fluctuations result in fewer water molecules cotransported with the ion in the second shell and a reduction in the length of the finger that the ion is attached to, consistent with the reduced size of the second hydration shell. First shell water residence time and lateral ion diffusion constants vary with the surface tension in a way that is consistent with the abovementioned structural insight.
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Affiliation(s)
- Ilan Benjamin
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, California 95064, United States
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10
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Kronberg R, Lappalainen H, Laasonen K. Revisiting the Volmer-Heyrovský mechanism of hydrogen evolution on a nitrogen doped carbon nanotube: constrained molecular dynamics versus the nudged elastic band method. Phys Chem Chem Phys 2020; 22:10536-10549. [PMID: 31998914 DOI: 10.1039/c9cp06474e] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Density functional theory (DFT) based computational electrochemistry has the potential to serve as a tool with predictive power in the rational development and screening of electrocatalysts for renewable energy technologies. It is, however, of paramount importance that simulations are conducted rigorously at a level of theory that is sufficiently accurate in order to obtain physicochemically sensible results. Herein, we present a comparative study of the performance of the static climbing image nudged elastic band method (CI-NEB) vs. DFT based constrained molecular dynamics simulations with thermodynamic integration in estimating activation and reaction (free) energies of the Volmer-Heyrovský mechanism on a nitrogen doped carbon nanotube. Due to cancellation of errors within the CI-NEB calculations, static and dynamic activation barriers are observed to be surprisingly similar, while a substantial decrease in reaction energies is seen upon incorporation of solvent dynamics. This finding is attributed to two competing effects; (1) solvent reorganization that stabilizes the transition and, in particular, the product states with respect to the reactant state and (2) destabilizing entropic contributions due to solvent fluctuations. Our results highlight the importance of explicitly sampling the interfacial solvent dynamics when studying hydrogen evolution at solid-liquid interfaces.
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Affiliation(s)
- Rasmus Kronberg
- Research Group of Computational Chemistry, Department of Chemistry and Materials Science, Aalto University, P.O. Box 16100, FI-00076 Aalto, Finland.
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11
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Das S, Imoto S, Sun S, Nagata Y, Backus EHG, Bonn M. Nature of Excess Hydrated Proton at the Water-Air Interface. J Am Chem Soc 2020; 142:945-952. [PMID: 31867949 PMCID: PMC6966913 DOI: 10.1021/jacs.9b10807] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Indexed: 01/02/2023]
Abstract
Understanding the interfacial molecular structure of acidic aqueous solutions is important in the context of, e.g., atmospheric chemistry, biophysics, and electrochemistry. The hydration of the interfacial proton is necessarily different from that in the bulk, given the lower effective density of water at the interface, but has not yet been elucidated. Here, using surface-specific vibrational spectroscopy, we probe the response of interfacial protons at the water-air interface and reveal the interfacial proton continuum. Combined with spectral calculations based on ab initio molecular dynamics simulations, the proton at the water-air interface is shown to be well-hydrated, despite the limited availability of hydration water, with both Eigen and Zundel structures coexisting at the interface. Notwithstanding the interfacial hydrated proton exhibiting bulk-like structures, a substantial interfacial stabilization by -1.3 ± 0.2 kcal/mol is observed experimentally, in good agreement with our free energy calculations. The surface propensity of the proton can be attributed to the interaction between the hydrated proton and its counterion.
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Affiliation(s)
- Sudipta Das
- Department
for Molecular Spectroscopy, Max Planck Institute
for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Sho Imoto
- Department
for Molecular Spectroscopy, Max Planck Institute
for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Shumei Sun
- Department
for Molecular Spectroscopy, Max Planck Institute
for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna, Austria
| | - Yuki Nagata
- Department
for Molecular Spectroscopy, Max Planck Institute
for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ellen H. G. Backus
- Department
for Molecular Spectroscopy, Max Planck Institute
for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna, Austria
| | - Mischa Bonn
- Department
for Molecular Spectroscopy, Max Planck Institute
for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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12
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Lentz J, Garofalini SH. Formation and migration of H3O+ and OH− ions at the water/silica and water/vapor interfaces under the influence of a static electric field: a molecular dynamics study. Phys Chem Chem Phys 2020; 22:22537-22548. [DOI: 10.1039/d0cp03656k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Water ‘layers’ 1 and 2 in pink; ‘layer’ 3 in blue and green over portion of glass surface (grey). +90° field causes water migration and clustering.
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Affiliation(s)
- Jesse Lentz
- Interfacial Molecular Science Laboratory
- Department of Materials Science and Engineering, Rutgers University
- USA
| | - Stephen H. Garofalini
- Interfacial Molecular Science Laboratory
- Department of Materials Science and Engineering, Rutgers University
- USA
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13
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Benjamin I. Hydronium ion at the water/1,2-dichloroethane interface: Structure, thermodynamics, and dynamics of ion transfer. J Chem Phys 2019; 151:094701. [DOI: 10.1063/1.5116008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ilan Benjamin
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, USA
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14
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Agmon N, Bakker HJ, Campen RK, Henchman RH, Pohl P, Roke S, Thämer M, Hassanali A. Protons and Hydroxide Ions in Aqueous Systems. Chem Rev 2016; 116:7642-72. [PMID: 27314430 DOI: 10.1021/acs.chemrev.5b00736] [Citation(s) in RCA: 294] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Understanding the structure and dynamics of water's constituent ions, proton and hydroxide, has been a subject of numerous experimental and theoretical studies over the last century. Besides their obvious importance in acid-base chemistry, these ions play an important role in numerous applications ranging from enzyme catalysis to environmental chemistry. Despite a long history of research, many fundamental issues regarding their properties continue to be an active area of research. Here, we provide a review of the experimental and theoretical advances made in the last several decades in understanding the structure, dynamics, and transport of the proton and hydroxide ions in different aqueous environments, ranging from water clusters to the bulk liquid and its interfaces with hydrophobic surfaces. The propensity of these ions to accumulate at hydrophobic surfaces has been a subject of intense debate, and we highlight the open issues and challenges in this area. Biological applications reviewed include proton transport along the hydration layer of various membranes and through channel proteins, problems that are at the core of cellular bioenergetics.
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Affiliation(s)
- Noam Agmon
- The Fritz Haber Research Center, Institute of Chemistry, The Hebrew University of Jerusalem , Jerusalem 91904, Israel
| | - Huib J Bakker
- FOM Institute AMOLF , Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - R Kramer Campen
- Fritz Haber Institute of the Max Planck Society , Faradayweg 4-6, 14195 Berlin, Germany
| | - Richard H Henchman
- Manchester Institute of Biotechnology, School of Chemistry, The University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom
| | - Peter Pohl
- Johannes Kepler University Linz , Institute of Biophysics, Gruberstrasse 40, 4020 Linz, Austria
| | - Sylvie Roke
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Material Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015, Lausanne, Switzerland
| | - Martin Thämer
- Fritz Haber Institute of the Max Planck Society , Faradayweg 4-6, 14195 Berlin, Germany.,Department of Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago , Chicago, Illinois 60637, United States
| | - Ali Hassanali
- CMSP Section, The Abdus Salaam International Center for Theoretical Physics , I-34151 Trieste, Italy
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15
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Ions interacting in solution: Moving from intrinsic to collective properties. Curr Opin Colloid Interface Sci 2016. [DOI: 10.1016/j.cocis.2016.05.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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16
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Bai C, Herzfeld J. Surface Propensities of the Self-Ions of Water. ACS CENTRAL SCIENCE 2016; 2:225-31. [PMID: 27163053 PMCID: PMC4850511 DOI: 10.1021/acscentsci.6b00013] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Indexed: 05/15/2023]
Abstract
The surface charge of water, which is important in a wide range of chemical, biological, material, and environmental contexts, has been a subject of lengthy and heated debate. Recently, it has been shown that the highly efficient LEWIS force field, in which semiclassical, independently mobile valence electron pairs capture the amphiproticity, polarizability and H-bonding of water, provides an excellent description of the solvation and dynamics of hydroxide and hydronium in bulk water. Here we turn our attention to slabs, cylinders, and droplets. In extended simulations with 1000 molecules, we find that hydroxide consistently prefers the surface, hydronium consistently avoids the surface, and the two together form an electrical double layer until neutralization occurs. The behavior of hydroxide can largely be accounted for by the observation that hydroxide moving to the surface loses fewer hydrogen bonds than are gained by the water molecule that it displaces from the surface. At the same time, since the orientation of the hydroxide increases the ratio of dangling hydrogens to dangling lone pairs, the proton activity of the exposed surface may be increased, rather than decreased. Hydroxide also moves more rapidly in the surface than in the bulk, likely because the proton donating propensity of neighboring water molecules is focused on the one hydrogen that is not dangling from the surface.
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17
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Partanen L, Murdachaew G, Gerber RB, Halonen L. Temperature and collision energy effects on dissociation of hydrochloric acid on water surfaces. Phys Chem Chem Phys 2016; 18:13432-42. [DOI: 10.1039/c6cp00597g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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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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19
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Duignan TT, Parsons DF, Ninham BW. Hydronium and hydroxide at the air–water interface with a continuum solvent model. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.06.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Baer MD, Kuo IFW, Tobias DJ, Mundy CJ. Toward a unified picture of the water self-ions at the air-water interface: a density functional theory perspective. J Phys Chem B 2014; 118:8364-72. [PMID: 24762096 DOI: 10.1021/jp501854h] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The propensities of the water self-ions, H3O(+) and OH(-), for the air-water interface have implications for interfacial acid-base chemistry. Despite numerous experimental and computational studies, no consensus has been reached on the question of whether or not H3O(+) and/or OH(-) prefer to be at the water surface or in the bulk. Here we report a molecular dynamics simulation study of the bulk vs interfacial behavior of H3O(+) and OH(-) that employs forces derived from density functional theory with a generalized gradient approximation exchange-correlation functional (specifically, BLYP) and empirical dispersion corrections. We computed the potential of mean force (PMF) for H3O(+) as a function of the position of the ion in the vicinity of an air-water interface. The PMF suggests that H3O(+) has equal propensity for the interface and the bulk. We compare the PMF for H3O(+) to our previously computed PMF for OH(-) adsorption, which contains a shallow minimum at the interface, and we explore how differences in solvation of each ion at the interface vs in the bulk are connected with interfacial propensity. We find that the solvation shell of H3O(+) is only slightly dependent on its position in the water slab, while OH(-) partially desolvates as it approaches the interface, and we examine how this difference in solvation behavior is manifested in the electronic structure and chemistry of the two ions.
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Affiliation(s)
- Marcel D Baer
- Physical Science Division, Pacific Northwest National Laboratory , Richland, Washington 99352, United States
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21
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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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22
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Hub JS, Wolf MG, Caleman C, van Maaren PJ, Groenhof G, van der Spoel D. Thermodynamics of hydronium and hydroxide surface solvation. Chem Sci 2014. [DOI: 10.1039/c3sc52862f] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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23
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Shapovalov VL, Möhwald H, Konovalov OV, Knecht V. Negligible water surface charge determined using Kelvin probe and total reflection X-ray fluorescence techniques. Phys Chem Chem Phys 2013; 15:13991-8. [PMID: 23842782 DOI: 10.1039/c3cp51575c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The water surface charge has been extensively debated in recent decades. Electrophoretic mobilities of air bubbles in water and disjoining pressures between the surfaces of aqueous films suggest that the surface of water exhibits a significant negative charge. This is commonly attributed to a strong adsorption of hydroxide ions at the interface, though spectroscopic measurements and simulation studies suggest surface depletion of hydroxide ions. Alternatively, the negative surface charge could arise from surface contamination with trace charged surfactants. We have probed the variation in the surface charge of water with pH by measuring surface potentials using the Kelvin probe technique. Independently, the abundance in the interfacial layer of "reporter ions" (Rb(+) and Br(-)), which must be affected by a charged surface, has been monitored using the total reflection X-ray fluorescence (TRXF) technique. Special care was taken to prove the high sensitivity of this technique as well as to avoid surface contaminants. The magnitude of the surface charge was found to be below 1 e per 500 nm(2) (TRXF). No evidence of variations in the surface potential between pH 2-3 and pH 9-12 was detected within the accuracies of the methods (5 mV for Kelvin probe and 2 mV for TRXF). Hence, our findings suggest that the clean water surface exhibits negligible charge in a wide pH range.
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24
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Tobias DJ, Stern AC, Baer MD, Levin Y, Mundy CJ. Simulation and Theory of Ions at Atmospherically Relevant Aqueous Liquid-Air Interfaces. Annu Rev Phys Chem 2013; 64:339-59. [DOI: 10.1146/annurev-physchem-040412-110049] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Douglas J. Tobias
- Department of Chemistry, University of California, Irvine, California 92697-2025; ,
| | - Abraham C. Stern
- Department of Chemistry, University of California, Irvine, California 92697-2025; ,
| | - Marcel D. Baer
- Chemical and Materials Science Division, Pacific Northwest National Laboratory, Richland, Washington 99352; ,
| | - Yan Levin
- Insituto de Física, Universidade Federal do Rio Grande do Sul, CEP 91501-970 Porto Alegre, RS, Brazil;
| | - Christopher J. Mundy
- Chemical and Materials Science Division, Pacific Northwest National Laboratory, Richland, Washington 99352; ,
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25
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Mella M. Exploring unvisited regions to investigate solution properties: The backyard of H3O+ and its aggregates. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2012.10.078] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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26
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Kumar R, Knight C, Voth GA. Exploring the behaviour of the hydrated excess proton at hydrophobic interfaces. Faraday Discuss 2013; 167:263-78. [DOI: 10.1039/c3fd00087g] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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27
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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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28
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Walewski Ł, Forbert H, Marx D. Revealing the Subtle Interplay of Thermal and Quantum Fluctuation Effects on Contact Ion Pairing in Microsolvated HCl. Chemphyschem 2012; 14:817-26. [DOI: 10.1002/cphc.201200695] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 10/23/2012] [Indexed: 11/07/2022]
Affiliation(s)
- Łukasz Walewski
- Lehrstuhl für Theoretische Chemie, Ruhr‐Universität Bochum, Universitätsstrasse 150, 44801 Bochum (Germany), Fax: (+49) 234‐32‐14045
| | - Harald Forbert
- Lehrstuhl für Theoretische Chemie, Ruhr‐Universität Bochum, Universitätsstrasse 150, 44801 Bochum (Germany), Fax: (+49) 234‐32‐14045
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr‐Universität Bochum, Universitätsstrasse 150, 44801 Bochum (Germany), Fax: (+49) 234‐32‐14045
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29
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Water at hydrophobic interfaces delays proton surface-to-bulk transfer and provides a pathway for lateral proton diffusion. Proc Natl Acad Sci U S A 2012; 109:9744-9. [PMID: 22675120 DOI: 10.1073/pnas.1121227109] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fast lateral proton migration along membranes is of vital importance for cellular energy homeostasis and various proton-coupled transport processes. It can only occur if attractive forces keep the proton at the interface. How to reconcile this high affinity to the membrane surface with high proton mobility is unclear. Here, we tested whether a minimalistic model interface between an apolar hydrophobic phase (n-decane) and an aqueous phase mimics the biological pathway for lateral proton migration. The observed diffusion span, on the order of tens of micrometers, and the high proton mobility were both similar to the values previously reported for lipid bilayers. Extensive ab initio simulations on the same water/n-decane interface reproduced the experimentally derived free energy barrier for the excess proton. The free energy profile G(H(+)) adopts the shape of a well at the interface, having a width of two water molecules and a depth of 6 ± 2RT. The hydroniums in direct contact with n-decane have a reduced mobility. However, the hydroniums in the second layer of water molecules are mobile. Their in silico diffusion coefficient matches that derived from our in vitro experiments, (5.7 ± 0.7) 10(-5) cm(2) s(-1). Conceivably, these are the protons that allow for fast diffusion along biological membranes.
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30
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Hammerich AD, Buch V. Ab Initio Molecular Dynamics Simulations of the Liquid/Vapor Interface of Sulfuric Acid Solutions. J Phys Chem A 2012; 116:5637-52. [DOI: 10.1021/jp2126398] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Audrey Dell Hammerich
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois
60607, United States
| | - Victoria Buch
- The Fritz
Haber Institute for Molecular Dynamics, The Hebrew University, Jerusalem 91904, Israel
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31
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32
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Takahashi H, Maruyama K, Karino Y, Morita A, Nakano M, Jungwirth P, Matubayasi N. Energetic Origin of Proton Affinity to the Air/Water Interface. J Phys Chem B 2011; 115:4745-51. [DOI: 10.1021/jp2015676] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hideaki Takahashi
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai Miyagi, 980-8578, Japan
| | - Kunihiro Maruyama
- Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka Osaka, 560-8531, Japan
| | - Yasuhito Karino
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Akihiro Morita
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai Miyagi, 980-8578, Japan
| | - Masayoshi Nakano
- Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka Osaka, 560-8531, Japan
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic and Center for Biomolecules and Complex Molecular Systems, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Nobuyuki Matubayasi
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
- Japan Science and Technology Agency (JST), CREST, Kawaguchi, Saitama 332-0012, Japan
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33
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Jagoda-Cwiklik B, Cwiklik L, Jungwirth P. Behavior of the Eigen Form of Hydronium at the Air/Water Interface. J Phys Chem A 2011; 115:5881-6. [DOI: 10.1021/jp110078s] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Barbara Jagoda-Cwiklik
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, and Center for Complex Molecular Systems and Biomolecules, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
| | - Lukasz Cwiklik
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, and Center for Complex Molecular Systems and Biomolecules, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, and Center for Complex Molecular Systems and Biomolecules, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
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34
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Wang Y, Hodas NO, Jung Y, Marcus RA. Microscopic structure and dynamics of air/water interface by computer simulations—comparison with sum-frequency generation experiments. Phys Chem Chem Phys 2011; 13:5388-93. [DOI: 10.1039/c0cp02745f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Bucher D, Gray-Weale A, Kuyucak S. Ab Initio Study of Water Polarization in the Hydration Shell of Aqueous Hydroxide: Comparison between Polarizable and Nonpolarizable Water Models. J Chem Theory Comput 2010; 6:2888-95. [DOI: 10.1021/ct1003719] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Denis Bucher
- School of Physics, University of Sydney, NSW 2006, Australia
| | | | - Serdar Kuyucak
- School of Physics, University of Sydney, NSW 2006, Australia
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36
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Arillo Flores OI, Bernal-Uruchurtu MI. Charge Separation Process in Water Clusters Containing HCl. Molecular Dynamics Study Using Semiempirical Hamiltonians. J Phys Chem A 2010; 114:8975-83. [DOI: 10.1021/jp101803r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Oscar Ivan Arillo Flores
- Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos 62209, Mexico
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37
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Esai Selvan M, Keffer D, Cui S, Paddison S. Proton transport in water confined in carbon nanotubes: a reactive molecular dynamics study. MOLECULAR SIMULATION 2010. [DOI: 10.1080/08927021003752887] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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38
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Ishiyama T, Morita A. Analysis of anisotropic local field in sum frequency generation spectroscopy with the charge response kernel water model. J Chem Phys 2010; 131:244714. [PMID: 20059106 DOI: 10.1063/1.3279126] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
A new flexible and polarizable water model based on the charge response kernel (CRK) theory is developed for the analysis of sum frequency generation (SFG) spectroscopy. The CRK model well describes several bulk water properties and SFG spectrum by molecular dynamics (MD) calculations. While the flexible and polarizable MD simulation generally adopts the short-range damping of intermolecular interaction, it is found that the same procedure is not adequate for the calculation of transition dipole in strongly hydrogen bonding environment. Accordingly, the improved calculation of the nonlinear susceptibility of water surface results in the positive imaginary part in the 3000-3200 cm(-1) region, which is consistent with recent phase-sensitive experiments. The mechanism of the positive region is attributed to the anisotropic local field effect induced by the orientational correlation of surface water.
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Affiliation(s)
- Tatsuya Ishiyama
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
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39
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Mundy CJ, Kuo IFW, Tuckerman ME, Lee HS, Tobias DJ. Hydroxide anion at the air–water interface. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.09.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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40
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Kritayakornupong C, Vchirawongkwin V, Rode BM. An ab initio quantum mechanical charge field molecular dynamics simulation of a dilute aqueous HCl solution. J Comput Chem 2009; 31:1785-92. [DOI: 10.1002/jcc.21469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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