Perturbation theory for fluids of non-spherical polarizable dipolar molecules

Citation
T. Boublik et J. Winkelmann, Perturbation theory for fluids of non-spherical polarizable dipolar molecules, MOLEC PHYS, 96(3), 1999, pp. 435-441
Citations number
32
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
MOLECULAR PHYSICS
ISSN journal
00268976 → ACNP
Volume
96
Issue
3
Year of publication
1999
Pages
435 - 441
Database
ISI
SICI code
0026-8976(19990210)96:3<435:PTFFON>2.0.ZU;2-2
Abstract
Wertheim's renormalized thermodynamic perturbation theory is extended to sy stems of the polarizable dipolar Kihara molecules and applied to the polari zable dipolar two-centre Lennard-Jones (LJ) fluid. In the third-order pertu rbation theory, the thermodynamic properties of the reference two-centre LJ fluids are evaluated via the thermodynamic functions of the corresponding system of the Kihara rod-like molecules. For the molecular distribution fun ction of the Kihara fluid the function of the corresponding Gaussian overla p model is substituted. From the second- and third-order perturbation terms (determined for the permanent dipole moment and constant isotropic polariz ability) the Pade approximant is formulated and its derivative used for the determination of the value of the effective dipole moment. The final value of the effective dipole moment is used to evaluate the electrostatic contr ibutions to the residual Helmholtz energy, pressure and internal energy. Fo r the given value of the permanent dipole moment the thermodynamic function s depend both on polarizability and elongation of the model considered (and on temperature and density). Fair agreement of the theoretical results wit h simulation data for the polarizable Stockmayer and polarizable dipolar 2c LJ fluids was found.