Quantum Corrections to the Virial Coefficients for Potentials with Hard Cores

Abstract

The leading quantum correction to the virial coefficients is calculated for the case where the intermolecular potential has a hard core. If the potential is bounded and continuous outside the core, the leading quantum correction to the second virial coefficient comes entirely from the region of the hard-core boundary, and depends only on the diameter of the core and the depth of the potential well at the core boundary. The leading quantum correction to the higher virial coefficients also involves the value of the classical radial distribution function at the core boundary. If the potential has discontinuities outside the core, these will give rise to additional first-order corrections.