Diffusion in vibrating-molecule liquids

Abstract

The self-diffusion coefficient for a homonuclear diatomic liquid of vibrating molecules, resembling nitrogen, but with a wide range of vibration frequencies, is determined by computer simulation for a wide range of liquid states. The values are found to differ little from those for the corresponding rigid-molecule liquid and are remarkably insensitive to the vibration even for very-low-frequency and large-amplitude vibrations. We do not believe that explicit inclusion of molecular flexibility is likely to materially affect the gross dynamical properties of a molecular liquid.