화학공학소재연구정보센터
Journal of Physical Chemistry B, Vol.117, No.17, 5222-5229, 2013
A Drude Polarizable Model for Liquid Hydrogen Sulfide
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 angle 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.