On the Relation Between the Effective Pair-potential and the Static Structure Factor in Liquid Metals

Accurate neutron diffraction measurements of the static structure factor S(Q) for small wave-vector transfers Q have been used to obtain the ‘coarse’ structure of the long-range part of the effective inter-particle potential in liquid aluminium, lead and bismuth. An extended version of the random phase approximation developed by Gaskell has been used. It is found that for Al and Pb the potential is of simple oscillatory nature while for Bi it is of ledge type. Finer details of the shape of the potential could not be evaluated. Methods to determine a good pair-potential by combining experimental results and molecular dynamics calculations are suggested.