The partial structure factors and pair distribution functions for liquid Ag2Te have been measured using the method of neutron diffraction and isotopic substitution. The partial structure factors are consistent with a melt in which the predominant interactions are ionic in nature and in which the small Ag+ ions are highly disordered and move rapidly through a more ordered Te2- sub-structure. A detailed comparison has been made between the structure of this liquid and that of liquid Ag2Se. It is observed that the main structural features of the two liquids are similar but a significant difference is observed in SAgAg(Q). The differences in the electronic properties of the two liquids are discussed in light of these results.

The partial structure factors and pair distribution functions of liquid Cu2Se have been determined by neutron diffraction with isotopic substitution. The structure shows characteristics typical of those of an ionic 2:1 melt consisting of Cu+ and Se2- ions with the cations moving through a more ordered Se2- sub-structure. A detailed comparison has been made with recent results obtained for liquid Ag2Se. The structure is similar although there is no evidence of the double peak structure in the cation-cation partial structure factor, SCuCu(Q), as has been found in SAgAg(Q) for liquid Ag2Se and, to a more limited extent, for liquid Ag2Te. There is also less order in the Se2- sub-structure based on a comparison of SSeSe(Q) and the Bhatia-Thornton concentration-concentration structure factor, SCC(Q), for the two liquids.

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With reference to dense ionic liquids like the alkali metal-alkali halide melts, , we present a study of the distribution of the excess electronic charge x in Coulomb systems with electronic degrees of freedom. Within the mean-spherical approximation to the restricted primitive model of ionic liquids, we demonstrate the stability of systems that exhibit a maximum separation of cationic charges, . The results are verified and illustrated by Monte Carlo simulations. We discuss the implications of the principle of maximum charge separation for the electronic structure and the thermodynamics of dense ionic liquids, possible additional applications and its limitations due to the neglect of quantum effects.

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