COMPUTATION OF ELASTIC AND DYNAMIC PROPERTIES OF THE LIQUID-PHASE OF NOBLE-METALS - ILLUSTRATING TYPICALLY FOR MOLTEN AG AND CU

The potential function as formulated by Bretonnet and Deroache is appl ied to liquid Cu and Ag to derive longitudinal and transverse phonon f requencies, the power spectrum, and the velocity autocorrelation funct ion. From these phonon frequencies the elastic constants are evaluated . They are also calculated with the help of Schofield's equations whic h are computed through the first and second derivatives of the potenti al energy. The values are found to be in satisfactory agreement with e ach other. The ratio of the areas in negative regions of the velocity correlation function for these f.c.c. packed liquids are found to be e qual to the ratio of their atomic weights. The characteristic frequenc ies calculated by several methods are in satisfactory agreement with e ach other. The nearest-neighbour distance obtained by different method s is also given. It is observed that the omega(L)(k) maximum occurs ar ound k(F), the Fermi wave vector. From the velocity of sound calculate d from the experimental compressibility and k(F) the omega(L)(k) maxim um is computed and is found to be in reasonable agreement with other v alues.