Ab Initio Calculations for Properties of Laves Phase V2m (M = Zr, Hf, Ta) Compounds

A first-principles plane-wave pseudopotentials method based on the density functional theory (DFT), is used to investigate the structural, mechanic and electronic of Laves phase V2M (M = Zr, Hf, Ta) compounds. It is found that V2Hf is mechanically unstable because this compound do not satisfy the conditionC_11-C_12> 0 below 6.27 GPa, it becomes stable beyond this pressure, the bulk modulus B revealing the largest B values for V2Ta compound which are the stable ground state phases according to the total energies. Also there is a strong interaction between V and V, the interaction between M (M = Zr, Hf, Ta) and V is more strong and between M and M is the strongest.