THE METAL-NON-METAL TRANSITION IN LIQUID ALLOYS

The model of liquid semiconductors proposed by Enderby and Barnes (199 0) is reviewed in the light of new experimental work and theoretical a nalysis. Particular attention is focussed on liquid silver chalcogenid es which have been intensively studied over the past few years. It is concluded that at stoichiometry, the mobility remains finite and that the reduced conductivity arises from charge transfer. Thus the Anderso n and related transitions are not significant so far as stoichiometric liquid semiconductors are concerned. The electronic properties are dr iven by chemical effects and suggest that the Molt-Hubbard model may b e the most appropriate starting point for a complete theory.