| abstract |
Mixed metal chalcogenides formed of lanthanide chalcogenides having the formula MLnX2 where M is selected from the group consisting of Ag, Cu and Au; Ln is one of the elements of the lanthanide family other than Pm and X is selected from the group consisting of S, Se and Te and having electrical properties that range from dielectrics to semiconductors to metallic conductors in a temperature range from -50 DEG C. to in excess of +100 DEG C. The lanthanide chalcogenides can be prepared by slow fusion of the basic elements such as silver, lanthanum and selenium, in substantially stoichiometric properties, in powder form under an extended time period at elevated temperature, e.g. 650 DEG C. to 700 DEG C. |