Structure factor computation of RbCl and RbBr

The generalized mean spherical model approximation is used to obtain the total direct correlation function using a solution similar to that of Waisman-Lebowitz (WL) inside the core. Outside the core a sum of Coulomb and Yukawa potential is taken as a perturbation in the MSM approximation. The partial structure functions are computed by means of Pearson-Rushbrooke relations. Using these PSF's the radial distribution functions are calculated. All these partial structure functions have equal positive values at the long wave limit and the oscillations of the total direct correlation functions are found to cease with increasing k as expected. This new method is a generalization of previous MSM results in the sense that more general forms for the direct correlation function are considered. In both the cases, the coefficients of all terms can be independently adjusted. The partial structure functions and the radial distribution functions so computed gives better agreement than the mean spherical model approximation with experimental and also with molecular dynamics calculations.