Phase correlations in the CuAlSe2-CuAlTe2 system

Alloys in the CuAlSe2–CuAlTe2 system were synthesized in BN‐crucibles in silica tubes under vacuum to obtain the corresponding phase equilibria. X‐ray powder diffraction and thermal analytic data of the T–x phase diagram revealed a complete solid solutions series in the subsolidus region. Within the CuAlSe2xTe2(1–x) system the refined lattice parameters a and c approximately obey the Vegard rule and also the cell volume and the heat of fusion confirm linear correlations with the composition of the mixed crystals. The anion position parameter calculated after S. C. Abrahams & J. L. Bernstein (uAB) and J. E Jaffe & A. Zunger (uJZ) is greater than 0.25 and reveals a linear dependence on composition. The liquidus part of the CuAlSe2xTe2(1–x) system with x < 0.35 exhibits vertical section behaviour with a ternary peritectic followed up by a ternary monotectic whereas the region with x > 0.35 shows quasibinary equilibria. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)