Electronic and Ionic Interactions Analyzed through Concentration and Charge Fluctuations in K::cKCL(l-:z:) Mixtures

A deeper insight into short, medium and long ranges behaviour of partial structure factors (PSF) measured in the rich metal domain of KxKCL(l-x) solutions as a function of composition shows up that structural changes are characterised by a non-linear perturbation of the screening properties prevailing in the pure metal liquid. Pseudopotential theory for describing the anion-conduction electron interaction, and perturbation calculations must be dropped. The correlation between long wavelength limits of PSF and thermodynamic is particularly difficult to unravel at k = 0. The structural changes observed in neutron diffraction indicate that a better understanding of these correlations consists in treating the correlation between charge fluctuations and atomic concentration fluctuations. §1. Approach and modelisation of the interactions and screening properties in pure liquids and in the mixture The microscopic behaviour of alkali metals and alkali-halide salts is quite well understood and modelised. For simple metal liquids, it is based on a one component plasma model or OCP model. l), 2) To reproduce static and dynamic correlations in MX salts, 3) the Fumi-Tosi potential 4l with rigid or polarisable ions is rather success