Analytical expressions for the correlation function of a hard sphere dimerfluid

A closed form expression is given for the correlation function of a hard sp here dimer fluid. A set of integral equations is obtained from Wertheim's m ultidensity Ornstein-Zernike integral equation theory with Percus-Yevick ap proximation. Applying the Laplace transformation method to the integral equ ations and then solving the resulting equations algebraically, the Laplace transforms of the individual correlation functions are obtained. By the inv erse Laplace transformation, the radial distribution function (RDF) is obta ined in closed form out to 3D (D is the segment diameter). The analytical e xpression for the RDF of the hard dimer should be useful in developing the perturbation theory of dimer fluids.