PRECISE EXPERIMENTAL-DETERMINATION OF THE STRUCTURE OF NOBLE-GASES - 2-BODY AND MANY-BODY CONTRIBUTIONS

It is shown that, from recent measurements, the static structure facto r S(k) in noble gas fluids can be determined with the precision of a f ew parts per thousand. Examples for argon at low density and krypton a t high density are discussed and comparison with theoretical calculati ons are reported. The low-density case is analysed and compared with t heory in terms of virial expansions, while at high density a refined m odified hypernetted chain (MHNC) theory, which includes the three-body interaction, is used for the calculations. From the comparison we can conclude that precise information on the detail of the structure of t he fluid and its connection with the microscopic interaction potential can be derived.