Composition-temperature phase diagram of BexZn1-xO from first principles

Density-functional calculations have been performed to obtain the composition-temperature phase diagram for the BexZn1-xO alloys. Consistent density-functional theory within local density approximation has been employed for relaxing the atomic structures, calculating the enthalpy of formation, and determining the lattice vibrational contributions to the free energy. The results show that lattice vibrations significantly reduce the critical temperature. The predicted phase diagram is consistent with the experimental observation that alloying Mg with BexZn1-xO suppresses phase separation. (C) 2010 Elsevier B.V. All rights reserved.