First-principles calculations of the structural, electronic and optical properties of AgGaS2 and AgGaSe2

被引：38

作者：

Chahed, A ^{[1
]}

Benhelal, O ^{[1
]}

Laksari, S ^{[1
]}

Abbar, B ^{[1
]}

Bouhafs, B ^{[1
]}

Amrane, N ^{[1
]}

机构：

[1] Univ Djillali Liabes Sidi Bel Abbes, Dept Phys, Computat Mat Sci Lab, Sidi Bel Abbes 22000, Algeria

来源：

PHYSICA B-CONDENSED MATTER | 2005年 / 367卷 / 1-4期

关键词：

density functional theory; local density approximation; electronic structure of semiconductors; optical properties;

D O I：

10.1016/j.physb.2005.06.007

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

The structural, electronic and optical properties of two chalcopyrite crystals, AgGaS2 and AgGaSe2, are studied using the full potential linearized augmented plane waves method within the local density approximation. Geometrical optimization of the unit cell (equilibrium volume, c/a ratio, internal parameter u, and bulk modulus) is in good agreement with experimental data. The energy gap is found to be direct for both materials and the nature of the gap crucially depends on the manner in which the Ga 3d, and Ag 4d electrons are treated as core or valence states. Results on band structures, density of states, and charge-density distributions are presented. We report also our results on optical properties like the complex dielectric functions and the refractive index n of the AgGaS2 and AgGaSe2 crystals. We analyze in detail the structures of the dielectric function observed in the studied energy region. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：142 / 151

页数：10

共 40 条

[1] CRYSTAL-STRUCTURE OF PIEZOELECTRIC NONLINEAR-OPTIC AGGAS2 [J].