AN ACCURATE METHOD OF DERIVING EFFECTIVE PAIR POTENTIAL FROM STRUCTURAL DATA OF LIQUID ALKALI-METALS

We have derived the effective pair potential of liquid sodium at 373 K from the experimental structural data using the inverse method propos ed by Reatto er al. (Phys. Rev. A 33 (1986) 3451) and shown that, to i mprove the accuracy and the efficiency of the method, it is necessary to obtain an accurate pair distribution function by performing the sim ulation for a large system with the pair potential truncated at a larg e cutoff distance and by extrapolating it carefully.