The stability and elastic constants of X2Ni3Si (X=Ti, Mo and W): The novel ternary metal silicides

The crystal structures of the four novel ternary metal silicides are discussed. The chemical bonding characteristics and full set of elastic constants were calculated by first principles calculations. The calculated formation enthalpy values indicate that they are thermodynamically stable structures. The calculated bulk modulus values range from 180 to 260 GPa, larger than many common Laves phases. We also find the scale relation between bulk modulus and C44. The Debye temperature, heat capacity of them are also systematically calculated and compared.