Mean Atomic Volume and Tg of CUx(AS0.4Se0.2Te0.4)100-x Glasses

Results of measurements of the mean atomic volume(V) and the glass transition temperature (Tg) for ten glass compositions of the As-Se-Te-Cu system have been reported and discussed. The compositions studied can be represented as Cux(As0.2Te0.4)100-x glasses, with the Cu content varying from 5 to 25 atomic precent (at%) In the V-x and Tg-x data a change in shape is observed at the composition with a Cu content of 16.67 at % A model seconding to which, with progressive increase in the Cu content, formation of CuAsSe2 abd CuAsTe structural units begin to form in place of some of the original As,Se,and As2Te2 structural units of the parent glass, is able to account satisfactorily the change in slope at a Cu content of 16.67 at % The persent results strengthen our earlier conclusions (1) from a study of the Cux(As0.4Se0.3Te0.3)100-x glasse