Elastic and electronic properties of a new MAX compound from first-principles calculations

Based on first-principles calculations, we have investigated the elastic properties and electronic structure of a new MAX compound (Cr0.5V 0.5)2GeC. The obtained lattice parameters agree very well with available experimental and theoretical data. Elastic constants are calculated, then the mechanical properties such as compressibility, ductility and stiffness, especially elastic anisotropy of (Cr0.5V 0.5)2GeC are discussed in detail. The calculated charge density and density of state exhibit a mixture of covalent and ionic features in (Cr0.5V 0.5)2GeC due to the strong hybridization of C 2p with Cr 5d and V 4d states. The coexistence of the stronger and stiffer Cr–C and V–C covalent bonds reveals the underlying mechanism for the higher bulk modulus of (Cr0.5V 0.5)2GeC.