Molecular dynamics for discontinuous potentials

Abstract

Compressibility factors and structure in terms of site-site and centre-centre radial distribution functions are obtained for several hard polyatomic molecular fluids by means of Discontinuous Molecular Dynamics. Linear molecules with 3, 4 and 5 atoms, tetrahedral and hexagonal molecules at various densities are studied. Compressibility factors are compared with convex body equations of state based in the Scaled Particle Theory. A Monte Carlo method is used to calculate the volume and surface area of the molecules. Radial distribution functions are compared with Monte Carlo and RISM results. Equivalence of Molecular Dynamics and Monte Carlo results is established as well as the suitability of Scaled Particle Theory equations to represent the thermodynamics of such systems.