Stability, elastic and electronic properties of ta₂n by first-principles calculations

Owing to exploring the influence of the N atoms ordering in Ta₂N compounds on their properties, the stability, elastic, and electronic properties of Ta₂N compounds (Ta₂N-I: P3ml and Ta₂N-II: P31m) were investigated using first-principles calculations based on density functional theory. Ta₂N-II is energetically favorable according to the enthalpy of formation. Elastic constants were employed to reveal the stronger resistance to deformation, but weaker anisotropy, in Ta₂N-II. A ductile-brittle transition was found between Ta₂N-I (ductile) and Ta₂N-II (brittle). The partial density of states showed a stronger orbital hybridization of Ta-d and N-p in Ta₂N-II, resulting in stronger covalent bonding. The charge density difference illustrated the interaction of the Ta-N bond and electron distribution of Ta₂N.