First-principles prediction of mechanical and bonding characteristics of new T2 superconductor Ta5GeB2

In the present paper, density functional theory (DFT) based first-principles methods are applied to investigate the mechanical and bonding properties of the newly synthesized T-2 phase superconductor Ta5GeB2 for the first time. The calculated lattice constants are in reasonable agreement with the experiment. The elastic constants (C-ij), bulk modulus (B), shear modulus (G), Young's modulus (Y), Poisson's ratio (v), Pugh ratio (G/B), and elastic anisotropy factor A of Ta5GeB2 are calculated and used to explore the mechanical behavior of the compound. To give an explanation of the bonding nature of this new ternary tetragonal system, the band structure, density of states, and Mulliken atomic population are investigated. The estimated Debye temperature and Vickers hardness are also used to justify both the mechanical and bonding properties of Ta5GeB2.(C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim