Document Type : Research

Authors

• maryam azizi ¹
• hamdollah salehi ²

¹ Department of Physics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran

² Associate Professor, Department of Physics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran.

Abstract

In this study, the structural and optical properties such as refractive index, extinction coefficient, absorption coefficient, reflection coefficient, and optical conductivity of the monoclinic crystalline structure compound Ag2SiS3 are investigated using theoretical calculations. The LDA approximation with the pseudo-potential method, and from the density of states diagram, the value of the band gap are 1.2 eV, 1.4 eV, and 2.37 eV, in the LDA and LDA+U and HSE approximations, respectively, were obtained with norm conserving pseudo-potential. Also, the calculated bulk modulus value were 81 GPa in LDA, 79.4 GPa in LDA+U, and 76.5 GPa in HSE approximation. Finally, the optical properties such as refractive index, extinction coefficient, absorption coefficient, reflection coefficient and optical conductivity were examined. From the examination of the optical properties, the optical gap value obtained from the absorption coefficient is in good agreement with the band gap value, which is Optical coefficients are different in different directions due to the anisotropy of the structure. The value of the optical gap that read from the absorption coefficient diagram in the approximation of LDA, LDA+U and HSE were 1.27 eV, 1.4 eV and 2.37 eV, respectively. Based on the optical investigations, this compound is useful in solar cells and optoelectronic materials.

Keywords

• DFT
• Chalcogenide
• Density of States
• Bulk Modul
• Optical Properties