TRENDS IN BINARY AND TERNARY NOBLE-METAL GERMANIUM ALLOYS

Among the noble-metal-germanium alloys, significant differences betwee n the electronic and thermodynamic properties are known. There are sim ilarities between the Cu and Au alloys and a different behaviour for t he Ag alloys. For the series of Cu-Ge, (Cu0.50-Ag0.50)-Ge, Ag-Ge, (Ag0 .50-Au0.50)-Ge, Au-Ge alloys, the electrical resistivities were measur ed from 1200-degrees-C down to the corresponding liquidus. To what ext ent the systematic trends are explained in the framework of the Faber- Ziman theory, including a calculation for ternary alloys, is discussed . The position and amplitude of the maximum of the resistivity versus concentration and of the minimum of the temperature coefficient of the resistivity versus concentration is discussed.