TOTAL-ENERGY STUDY OF ELECTRONIC-STRUCTURE AND MECHANICAL-BEHAVIOR OFC15 LAVES PHASE-COMPOUNDS - NBCR2 AND HFV2

First-principles electronic structure calculations based on a full-pot ential linear muffin-tin orbital method have been used to study the el ectronic and mechanical properties of the early transition metal C15 L aves phase compounds NbCr2 and HfV2. For both compounds, total energie s are computed and compared for the two Laves phase crystal structures C15 and C14. The lower total-energy structure for NbCr2 is found to b e the C15 structure as opposed to the C14 structure for HfV2. We have calculated the equilibrium unit cell volumes, bulk moduli, cohesive en ergies, and heats of formation. We have obtained the density of states and charge density contour plots. Based on these results, we discuss the elastic properties, the stability of the C15 phase, and the bondin g and deformation mechanisms in Laves phases.