A systematic Monte Carlo (MC) simulation and perturbation theoreticalud (PT) study is reported for the dielectric constant of the polarizable dipolarud hard sphere (PDHS) fluid. We take the polarizability of the moleculesud into account in two different ways. In a continuum approach we place theud permanent dipole of the molecule into a sphere of dielectric constant Ɛ∞ud in the spirit of Onsager. The high frequency dielectric constant Ɛ∞ is calculatedud from the Clausius-Mosotti relation, while the dielectric constant ofud the polarizable fluid is obtained from the Kirkwood-Frohlich equation. In the molecular approach, the polarizability is built into the model on the molecularud level, which makes the interactions non- pairwise additive. Here weud use Wertheim’s renormalized PT method to calculate the induced dipoleud moment, while the dielectric constant is calculated from our recently introducedud formula [22]. We also apply a series expansion for the dielectricud constant both in the continuum and the molecular approach. These seriesud expansions ensure a better agreement with simulation results. The agreementud between our MC data and the PT results in the molecular approachud is excellent for low to moderate dipole moments and polarizabilities. Atud stronger dipolar interactions ergodicity problems and anizotropic behaviourud appear where simulation results become uncertain and the theoretical approachud becomes invalid.
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