Self-diffusion in a fluid of square-well spheres

Abstract

The self-diffusion coefficients for a dense fluid of particles interacting with a square-well potential are described. The expression for self-diffusion coefficients obtained by the Chapman–Enskog method of solution is corrected by the molecular dynamics simulation data. The structural data for the square-well fluid required in the calculation are obtained from explicit analytic equations for the radial distribution function. The corrected equation represents the self-diffusion coefficients with an average absolute deviation of 4.63% for the square-well fluid. The results are compared with those of other expressions. In addition, the self-diffusion coefficients for real fluids composed of simple, near spherical molecules are correlated using the square-well potential, and acceptable agreement is obtained between the calculated and experimental diffusion data.