The Stokes-Einstein Relation for Non-spherical Molecular Liquids

Abstract

The Stokes-Einstein (SE) relation for pure liquids of various non-spherical molecules is examined using molecular dynamics simulation. The SE relation obeys generally the equation recently proposed for simple liquids such as noble gases. The result shows that effects of molecular shape on self-diffusion coefficient and shear viscosity are negligible or cancel out in their product and the SE relation does not need concepts of the hydrodynamic particle size or the boundary condition as well as simple liquids. The Stokes-Einstein (SE) relation for pure liquids of various non-spherical molecules is examined using molecular dynamics simulation. The SE relation obeys generally the equation recently proposed for simple liquids such as noble gases. The result shows that effects of molecular shape on self-diffusion coefficient and shear viscosity are negligible or cancel out in their product.