Accession Number : ADA294314

Title :   The Role of Solvent Dipole Structure on the Capacitance on Charged Interfaces.

Descriptive Note : Technical rept. no. 2, Jun-Dec 94,

Corporate Author : UTAH UNIV SALT LAKE CITY DEPT OF CHEMISTRY

Personal Author(s) : Gao, Xiaoping ; White, Henry S.

PDF Url : ADA294314

Report Date : 31 MAR 1995

Pagination or Media Count : 25

Abstract : An electrostatic model of solvent (H20) dipole interactions at charged interfaces is reported. The model of H20 used in the present study has an internal dipole structure characterized by both a dipole moment (uD) and a finite dipole length (du) The electric force acting on an individual molecule in the first monolayer is computed as a function of du, taking into account both surface charge/dipole and dipole/dipole interactions. Inclusion of the finite dimensions of the dipole and hard-core solvent diameter allows a simple and self-consistent method for calculating the interaction between solvent molecules. The capacitance of the charged interface, based on a simplistic two state model of H20 orientation, is shown to be sensitive to the dipole structural parameters uD and du, demonstrating the necessity of accounting for the charge distribution within the solvent molecule. The results are discussed in terms of existing models of H20 currently used in molecular dynamics and Monte Carlo simulations of interfacial fluid structure.

Descriptors :   *ELECTROCHEMISTRY, *CAPACITANCE, *DIPOLE MOMENTS, SIMULATION, DIAMETERS, DISTRIBUTION, INTERFACES, LAYERS, MOLECULES, WATER, MONTE CARLO METHOD, CONSISTENCY, INTERNAL, DIPOLES, ELECTRIC POWER, SOLVENTS, MOLECULAR PROPERTIES, ELECTROSTATICS.

Subject Categories : Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE