Theoretical investigations of the physical properties of zircon-type YVO4

The crystal structure, electronic properties, elastic properties, hardness and thermodynamic properties of the laser host material zircon-type YVO4 are studied using the pseudopotential plane wave method within the local density approximation (LDA) and generalized gradient approximation (GGA). The calculated ground state values such as lattice parameter, bulk modulus and its pressure derivative, the band structure and densities of states were in favorable agreement with previous works and the existed experimental data. The elastic constants Cij, the aggregate elastic moduli (B, G, E), Poisson's ratio and elastic anisotropy have been investigated. In YVO4, V–O bonds with shorter bond length and larger Mulliken population make great contribution to hardness than Y–O bonds. Using quasi-harmonic Debye model considering the phonon effects, bulk modulus, heat capacity and thermal expansion coefficient of YVO4 are calculated within a range of 0–6GPa and 0–1200K. (a) Directional dependence of Young's modulus in zircon-type YVO4 and (b) projections of the directional dependent Young's modulus in different planes for zircon-type YVO4. The units are in GPa. [Display omitted] ► This paper systematically studied the physical properties of zircon-type YVO4 from first-principles calculations. ► Zircon-type YVO4 is mechanically stable and it is ductile for B/G>1.75 and v>0.26. ► Universal elastic anisotropy index AU for zircon-type YVO4 is 2.41, so YVO4 is anisotropic. ► V–O bonds with shorter bond length and larger Mulliken population make greater contribution to the hardness of YVO4.