Theoretical study of structural, electronic and optical properties of ScxTl1-xP ternary alloys and (ScP)n/(TlP)n superlattices by FP-LMTO method

Abstract The Full Potential Linear Muffin-Tin Orbital (FP-LMTO) method has been used to investigate structural and electronic properties of ScP and TlP binary compounds, their Sc x Tl 1-x P ternary alloys and (ScP) n /(TlP) n superlattices for specific cases of x = 0.25, 0.5, 0.75 and n = 1, 2, 3 in the framework of the density functional theory (DFT) within the local density approximation (LDA). The ground-state properties are determined in the cubic Zinc-blende phase (ZnS). The electronic band structures of Sc x Tl 1-x P ternary alloy were calculated in the Zinc-blende phase and the material has a semi-conductor behavior with a direct band gap for x = 0.25 and an indirect band gap for x = 0.5 and 0.75. In studying the possibility to obtain new materials (ScP) n /(TlP) n , the results show that these materials are semiconductors with an indirect band gap for n = 1 and a direct band gap for n = 2 and 3. The optical properties were calculated for only three materials; Sc 0.25 Tl 0.75 P, (ScP) 2 /(TlP) 2 and (ScP) 3 /(TlP) 3 which have a direct band gap.