Y.L. Du

Phase stability and elastic properties of graphene-like Tan+1Cn (n = 1, 2, or 3) from first-principles calculations

Abstract In this work, the elastic properties and relative stability of graphene-like Tan+1Cn monolayers have been studied by first-principles calculation. The lattice constants, thickness of monolayer, density of states, and charge transfer of Tan+1Cn monolayers were calculated and compared with the [Tan+1Cn] block in the parent MAX phase. The phase stability of Tan+1Cn monolayers was investigated in terms of their cohesive energies. It was found that the relative stability of Tan+1Cn monolayers increased with increasing the value of n. Based on the Bader charge analysis, the nature of bonding of Tan+1Cn was revealed to be combination of covalent and ionic. Moreover, the elastic constant c 11 and c 12, the in-plane stiffness and Poissons ratio of Tan+1Cn monolayers were also determined. The results indicate that graphene-like Tan+1Cn are extremely stiff materials compared with other two-dimensional materials.