Electronic density of states for liquid metals and alloys in the tight binding approximation

The tight binding approximation for d electrons in liquid metals first studied by Roth (1972) using multiple scattering theory is re-examined by a diagrammatic analysis and is rederived by a new method and also extended to liquid metal alloys. The diagrammatic analysis permits a simple physical interpretation of the multiple scattering theory discussed by Schwartz and Ehrenreich (1971). Using a selfconsistent approximation the authors derive expressions for the electronic density of states N(E) using various approximations for the atomic correlation functions. In particular, it is shown that for a correlated liquid treated within SCA the electronic self energy Sigma (E) can be decomposed quite generally into a local and a non local part and that only the local part of Sigma (E) contributes to N(E).