On the Kinetic Theory of Dense Fluids. VI. Singlet Distribution Function for Rigid Spheres with an Attractive Potential

Abstract

A new integro‐differential equation for the singlet distribution function in a model dense fluid is derived and solved. In the model considered, the pair interaction potential is represented as a rigid core plus a soft attraction. Interactions between two rigid cores are handled as in the theory of the dense rigid‐sphere fluid, while interactions between the soft attractions are handled, following Kirkwood, in the Fokker‐Planck approximation. The use of coarse graining in time to provide a time scale permitting the above separation, the relaxation in momentum space, the kinetic flux vectors, and the physical basis of the analysis are all discussed.