By the application of an ab initio density functional approach the structural and phase stabilities, enthalpies of formation, electronic structures, and elastic properties for the isoelectronic Laves phase compounds ${\mathrm{TiCr}}_2,{\mathrm{ZrCr}}_2$, and ${\mathrm{HfCr}}_2$ in the cubic C15, and hexagonal C14 and C36 structures have been investigated. In addition, for the C14 and C15 structures of ${\mathrm{ZrCr}}_2$ phonon dispersions and densities of states, temperature dependent free energies, and point defect properties have been derived from ab initio calculations. The comparison of the density functional data to the few existing experimental results proves the validity of the ab initio approach. Results for ${\mathrm{ZrCr}}_2$ and ${\mathrm{ZrMn}}_2$ are compared in order to corroborate the structural degeneracy for ${\mathrm{ZrMn}}_2$ as predicted recently.

• Received 21 November 2004
• Corrected 9 May 2005

DOI:https://doi.org/10.1103/PhysRevB.71.174101