Mechanical, Anisotropic, and Electronic Properties of XN (X = C, Si, Ge): Theoretical Investigations.

The structural, mechanical, elastic anisotropic, and electronic properties of -XN (X = C, Si, Ge) are investigated in this work using the Perdew-Burke-Ernzerhof (PBE) functional, Perdew-Burke-Ernzerhof for solids (PBEsol) functional, and Ceperly and Alder, parameterized by Perdew and Zunger (CA-PZ) functional in the framework of density functional theory. The achieved results for the lattice parameters and band gap of -CN with the PBE functional in this research are in good accordance with other theoretical results. The band structures of -XN (X = C, Si, Ge) show that -SiN and -GeN are both direct band gap semiconductor materials with a band gap of 3.39 eV and 2.22 eV, respectively. -XN (X = C, Si, Ge) exhibits varying degrees of mechanical anisotropic properties with respect to the Poisson's ratio, bulk modulus, shear modulus, Young's modulus, and universal anisotropic index. The (001) plane and (010) plane of -CN/SiN/GeN both exhibit greater elastic anisotropy in the bulk modulus and Young's modulus than the (100) plane.