Numerical solution of RISM for homonuclear vibrating hard-dumbells

Abstract

Numerical solutions of the reference interaction site model (RISM) for site-site radial distribution functions gαβ(r) of a fluid of vibrating harddumbells are carried out, using a method of direct substitution in Fourier space. Comparisons with molecular dynamics (MD) results for the same system are given. The intramolecular distribution functions obtained by MD are used in RISM to obtain the corresponding intermolecular site-site gαβ(r), which in turn are compared against the MD results. These numerical results and further algebraic analysis indicate that the intermolecular site-site correlation functions calculated with RISM, do not depend noticeably on the form of the intramolecular correlation function used in the calculation. Additional evidence on the equivalence of vibrating and rigid hard dumbells is given.