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Parfenyuk, V. I.

doi:10.1023/a:1020614010528

Cited by 46 publications

(44 citation statements)

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“…This difference in electrostatic potential, termed the interfacial potential, results from a net orientation of dipole moments (both permanent and induced for all solution components) in addition to a quadrupole moment contribution (permanent and induced) arising from the distribution, orientation and density of water molecular quadrupole moments. While this property is conveniently accessible in simulation, consensus experimental estimates of the interfacial potential (even for pure water) remain in dispute and include both positive and negative values that span an approximate ±1500 mV range around zero (see references 97 and 98 and the references contained therein). In contrast, a number of recent theoretical determinations of the inter facial potential of water derived from molecular dynamics simulations employing a variety of water models and simulation protocols typically report consistent values on the order of -400 to -600 mV (discussed below).…”

Section: Resultsmentioning

confidence: 99%

Electrostatic Properties of Aqueous Salt Solution Interfaces: A Comparison of Polarizable and Nonpolarizable Ion Models

Warren

Patel

2008

J. Phys. Chem. B

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The effects of ion force field polarizability on the interfacial electrostatic properties of ~1 M aqueous solutions of NaCl, CsCl and NaI are investigated using molecular dynamics simulations employing both non-polarizable and Drude-polarizable ion sets. Differences in computed depth-dependent orientational distributions, “permanent” and induced dipole and quadrupole moment profiles, and interfacial potentials are obtained for both ion sets to further elucidate how ion polarizability affects interfacial electrostatic properties among the various salts relative to pure water. We observe that the orientations and induced dipoles of water molecules are more strongly perturbed in the presence of polarizable ions via a stronger ionic double layer effect arising from greater charge separation. Both anions and cations exhibit enhanced induced dipole moments and strong z alignment in the vicinity of the Gibbs dividing surface (GDS) with the magnitude of the anion induced dipoles being nearly an order of magnitude larger than those of the cations and directed into the vapor phase. Depth-dependent profiles for the trace and zz components of the water molecular quadrupole moment tensors reveal 40% larger quadrupole moments in the bulk phase relative to the vapor mimicking a similar observed 40% increase in the average water dipole moment. Across the GDS, the water molecular quadrupole moments increase non-monotonically (in contrast to the water dipoles) and exhibit a locally reduced contribution just below the surface due to both orientational and polarization effects. Computed interfacial potentials for the non-polarizable salts yield values 20 to 60 mV more positive than pure water and increase by an additional 30 to 100 mV when ion polarizability is included. A rigorous decomposition of the total interfacial potential into ion monopole, water and ion dipole, and water quadrupole components reveals that a very strong, positive ion monopole contribution is offset by negative contributions from all other potential sources. Water quadrupole components modulated by the water density contribute significantly to the observed interfacial potential increments and almost entirely explain observed differences in the interfacial potentials for the two chloride salts. By lumping all remaining non-quadrupole interfacial potential contributions into a single “effective” dipole potential, we observe that the ratio of quadrupole to “effective” dipole contributions range from 2:1 in CsCl to 1:1.5 in NaI suggesting that both contributions are comparably important in determining the interfacial potential increments. We also find that oscillations in the quadrupole potential in the double layer region are opposite in sign and partially cancel those of the “effective” dipole potential.

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Section: Resultsmentioning

confidence: 99%

Electrostatic Properties of Aqueous Salt Solution Interfaces: A Comparison of Polarizable and Nonpolarizable Ion Models

Warren

Patel

2008

J. Phys. Chem. B

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“…1). This is explained by the difference of physicochemical and electrochemical properties of the bulk (vol ume) and the surface of solution [5][6][7][8][9][10] that are directly related to the structural peculiarities of water as a sol vent [11,12].…”

Section: Resultsmentioning

confidence: 99%

On the transformation of trichloroacetic acid in aqueous media

Pershina

Kazdobin

2014

J. Water Chem. Technol.

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The influence of the chemical composition of water on the rate of volatilization and degrada tion of trichloroacetic acid (TCA) has been investigated. The schemes of possible secondary pollution of territories adjacent to the polluted water bodies were discussed on the basis of measuring the surface ten sion, TCA distribution in solution, and the analysis of kinetic parameters of its volatilization and oxida tion.

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“…In spite of a great body of information on the surface potential of water accumulated to date, the sign and numerical value of this parameter is still debat able. The χ(H 2 O) values reported by different authors vary from -1.1 to +0.5 V. 3 Analysis of these data suggests that the surface poten tial of water equal to +0.10 V seems to be the best ap proximation at the moment. The positive sign of this pa rameter is substantiated by the fact that the negative ends of water dipoles are oriented toward the gas phase while their positive ends are oriented toward the liquid phase.…”

Section: The Surface Potentials Of Water and Nonaqueous Solventsmentioning

confidence: 88%

Application of Volta chains to determine ionic components of real and chemical Gibbs energies of transfer of individual ions from water to aqueous-organic solvents

Parfenyuk

2007

Russ Chem Bull

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The state of individual ions in individual and mixed solvents was described from the thermodynamic point of view using the method of Volta potential differences. This method ology provides a way of solving the problem of determination of thermodynamic characteristics of individual ions in solutions. The possibility of using the method of Volta potential differences to determine the ionic components of the real and chemical thermodynamic properties of individual ions in solutions and the surface potentials at gas-solution interface is substan tiated.

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Cited by 46 publications

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Electrostatic Properties of Aqueous Salt Solution Interfaces: A Comparison of Polarizable and Nonpolarizable Ion Models

Electrostatic Properties of Aqueous Salt Solution Interfaces: A Comparison of Polarizable and Nonpolarizable Ion Models

On the transformation of trichloroacetic acid in aqueous media

Application of Volta chains to determine ionic components of real and chemical Gibbs energies of transfer of individual ions from water to aqueous-organic solvents

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