Eur. Phys. J. B 72, 361-366 (2009)
https://doi.org/10.1140/epjb/e2009-00345-6

First-principles study of structural, electronic, linear and nonlinear optical properties of Ga₂PSb ternary chalcopyrite

¹ Laboratoire de Physique Théorique, B.P. 119, Université de Tlemcen, 13000 Tlemcen, Algeria
² Institute of Physical Biology, South Bohemia University, 37333 Nove Hrady, Czech Republic
³ Departamento de Química Física y Analítica. Universidad de Oviedo, 33006 Oviedo, Spain
⁴ Laboratoire de Physique Quantique et de Modélisation Mathématique, Université de Mascara, 29000 Mascara, Algeria

Corresponding authors: ^a tarik_ouahrani@hotmail.com - ^b maalidph@yahoo.co.uk

Received: 28 July 2009
Published online: 13 October 2009

Abstract

We report results from first-principles density functional calculations using the full-potential linear augmented plane wave (FP-LAPW) method. The generalized gradient approximation (GGA) and the Engel-Vosko-generalized gradient approximation (EV-GGA) were used for the exchange-correlation energy of the structural, electronic, linear and nonlinear optical properties of the chalcopyrite Ga₂PSb compound. The valence band maximum (VBM) is located at the Γ_v point, and the conduction band minimum (CBM) is located at the Γ_c point, resulting in a direct band gap of about 0.365 eV for GGA and 0.83 eV for EV-GGA. In comparison with the experimental one (1.2 eV) we found that EV-GGA calculation gives energy gap in reasonable agreement with the experiment. The spin orbit coupling has marginal influence on the optical properties. The ground state quantities such as lattice parameters (a, c and u), bulk modules B and its pressure derivative B^′are evaluated.