BINARY A(III) NITRIDE SOLID-SOLUTIONS - ESTIMATION OF THE EXCESS GIBBS ENERGY

Empirical correlations between the excess Gibbs energy interaction par ameters and the molar volume or the nearest neighbour distance differe nces were used to estimate the excess thermodynamic properties of the mixed A(III) nitrides. Using the two coefficient Redhlich-Kister equat ion the values of a symmetric parameter L-0 obtained by the correlatio ns are almost the same. On the other hand the value of an asymmetric p arameter L-1 for the molar volume differences correlation is always gr eater than in the case of the nearest neighbour distance differences. The estimated values of interaction parameters indicate that the AlN-G aN binary system is nearly ideal while indium containing mixed nitride s exhibit large positive deviations from ideal behaviour. (C) 1997 Els evier Science Ltd. All rights reserved.