Significant-Structure Theory and Cell Theory for Two-Dimensional Liquids of Hard Disks

The significant-structure theory of liquids is applied to describe a two-dimensional liquid of hard disks. The results are in quite good agreement with the molecular-dynamics calculations. However, the virial expansion of the equation of state is in only fair agreement with the machine calculations. Cell theory is also applied to the two-dimensional liquid; it is found that although the agreement with the molecular-dynamics data is poor in the liquid range, the cell theory shows good agreement in the solid region.