First-principles studies of the structural, elastic, electronic and thermal properties of Ni₃Nb

First-principles calculations were performed to investigate the structural, elastic, electronic and thermal properties of Ni₃Nb. The calculated results are agreed well with the available experimental data. The chemical bonding was interpreted by calculating the density of states, electron density distribution and Mulliken analysis. Ni₃Nb has a combination of metallic, ionic and covalent bonding properties. Elastic constants were calculated, and the bulk modulus, shear modulus, Young's modulus and Poisson's ratio of polycrystalline aggregates were derived. The value of B/G is bigger than 1.75 and the material is ductile. Electronic density of states (DOSs) and charge density distribution were also calculated to reveal the underlying mechanism of structural stability and mechanical properties. Moreover, the pressure and temperature dependences of thermal expansion coefficient, bulk modulus, Debye temperature and heat capacity in a wide pressure (0-40 GPa) and temperature (0-1600 K) ranges are presented in this study.