Molecular Dynamics Study of the Structure of Expanded Liquid Caesium

The density dependence of the structure of liquid Cs expanded along the liquid-vapour coexistence curve is studied by the molecular dynamics (MD) simulation based on the effective pair potential calculated by the pseudopotential theory. The obtained pair correlation functions are compared with the recent neutron diffraction experiment due to Winter et al . and with the theoretical results in the modified hypernetted-chain (MHNC) approximation. It is shown that the characteristic features of the density dependence of the MD results agree well with the experimental ones and that the MD results are in excellent agreement with the MHNC results. The characteristic features of the atomic arrangements are also investigated by using the Voronoi tessellation.