Effect of core nonsphericity on the entropy of simple liquids

The lowering of the entropy of simple liquids due to the nonspherical shape of the repulsive molecular cores was estimated quantitatively from a generalized van der Waals equation. For the liquids considered, the entropy lowering relative to an equivalent hard sphere liquid was found to be in the range 0.1R to 0.3R. Such a small decrease can be explained as due to partial compensation of the loss of orientational disorder and the gain in packing disorder which arise from nonsphericity.