title: A Drude polarizable model for liquid hydrogen sulfide.
abstract: A polarizable force field for liquid hydrogen sulfide (H2S) has been developed based on the Drude oscillator model. This force field has been designed to be analogous to the SWM4-NDP water model; the model is rigid with point charges assigned to the H and S atoms and a lone pair on the bisector of ∠HSH in the molecular plane. Positions of the lone pair and the charges have been defined such that the model has a static dipole moment of 0.98 D, equal to the experimental value. Polarizability is incorporated by a charged (Drude) particle attached to the S atom through a harmonic potential. Intermolecular nonbonded forces are included by use of a Lennard-Jones potential between S atoms. The model was parametrized to reproduce the density, enthalpy of vaporization, and dielectric constant of pure H2S at 212 K and 1 atm. The calculated density, enthalpy of vaporization, shear viscosity coefficient, and self-diffusion coefficient are in good agreement with experiment over the temperature range 212-298 K along the liquid-vapor coexistence curve of liquid H2S. The radial distribution function calculated from this model is in good agreement with experimental diffraction data and ab initio molecular dynamics simulations.
authors.affiliation: Department of Chemistry, Memorial University of Newfoundland, St. John's, Newfoundland A1B 3X7, Canada.
authors.forename: Saleh
authors.initials: S
authors.lastname: Riahi
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Rowley