Sphericalization of nonspherical interactions

Abstract
A density and temperature‐independent spherically symmetric reference potential is constructed for an interacting classical fluid of nonspherical molecules. It annuls the first order correction to the free energy and, in special cases, the second as well. The potential is a limiting form of that used successfully for N2 by Shaw et al., and reproduces numerically the Y4 approximation of Barboy and Gelbart for homonuclear dumbbell molecules.