First-principle study of structural and electronic properties of ternary layered Ta2AlC

The structural and electronic properties of ternary layered Ta2AlC ceramics have been studied using the first-principle method based on the density-functional theory. We have obtained the equilibrium lattice parameters and the equilibrium atomic positions in the unit cell. The equilibrium lattice parameters are computed to be a = b = 3.15 angstrom and c = 13.95 angstrom. The internal coordinates of Ta are determined to be (1/3, 2/3, 0.092). The band structure and density of states reveal that Ta2AlC is an electronic conductor. The charge density distribution shows that the Ta and C atoms form a strong Ta-C-Ta covalently bonded chain. (C) 2011 Elsevier Ltd. All rights reserved.