Étude de premiers principes des alcalin-pnictogènes sous l’effet de la pression hydrostatique

Abstract

The aim of this work is to study pressure effet on the structural and electronic properties of the Li2N aSb and Li2N aBi semiconductors using the Full Potential Linearized Augmented Plane Waves (FP-LAPW) in the frame work of the density functional theory (DFT) within the generalized gradient approximation (GGA). The obtained results of the sructural properties such as lattice parameters, bulk moduli agree well with other published results. The electronic structure and density of state confirm that all of the stidied compomds are indirect band gap semiconductors (Γ − X) witch is not affected by pressure. The direct and indrect band gaps increase on an quadratic polynomial of pressure. Pressure don’t change the interatomique bonds, they are ionic betewen (Li-Na) atom and iono–covalente betwen (Li − Sb) and (Li − Bi