TOTAL AND PARTIAL STRUCTURE FACTORS, COMPRESSIBILITY, DIFFUSION-COEFFICIENTS AND OTHER ASSOCIATED PROPERTIES OF AN AG-SE SEMICONDUCTING ALLOY

Ashcroft-Langreth partial structure factors were computed using a Lebo witz solution of hard sphere mixtures perturbed by a square well poten tial. The potential parameters were obtained from the measured structu re factor. Both the partial and total structure factors were Fourier t ransformed to give the partial and total radial distribution functions , from which the partial and total numbers of nearest neighbours were evaluated. Using the peaks of the radial distribution functions the ne arest-neighbour distance was obtained. The results so obtained are fou nd to be in good agreement with experimentally determined values. The Bhatia-Thoronton correlation functions S-NN(k), S-CC(k) and S-NC(k), w ere calculated. It was found that S-NN(k) gives a maximum at a similar value of k as S-Total(k), as has been observed previously for the Ca0 .6Ag0.4 alloy. The compressibility, calculated using Kirkwood-Buffs eq uation, even though it appears to be high, is attributed to the migrat ion of silver atoms into voids in the liquid selenium. The selfdiffusi on coefficients were calculated, and that for silver was found to be h igher than that for selenium. These values are also attributed to the migration of the heavy silver atoms into the voids of the comparativel y less heavy selenium.