First-Principles Simulation of Structural, Electronic and Optical Properties of Cerium Trisulfide (Ce₂S₃) Compound

Abstract

In this work, the structural, electronic and optical properties of Ce₂S₃ compound have been explored using CASTEP simulation code. We explore the crystal structure, lattice parameters, electronic band structure, the total density of states (TDOS), the partial density of states (PDOS) and the optical functions of the Ce₂S₃ compound using first-principles simulation based on density functional theory (DFT). The orthorhombic crystal structure with space group (Pnma) of Ce₂S₃ is stable both chemically and structurally. The lattice parameters of this compound are obtained by the optimization method. The lattice parameters measured in this study (a = 7.53 Å, b = 4.10 Å and c = 15.73 Å) indicate excellent agreement with experimental and previous theoretical results. The electronic properties are investigated using Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) and GGA  observe  U approaches within DFT employing CASTEP code. The energy bandgap value reported in this study (E_g = 0.76 eV) is comparable to the previous theoretical value. This energy bandgap value shows that Ce₂S₃ belongs to the semiconductor category. The frequency-dependent dielectric function and some optical properties such as reflectivity, absorption coefficient, optical dielectric constant, optical conductivity and the energy loss function have also been calculated in the present work. The optical reflectivity is noted to be maximum in the ultraviolet region of the electromagnetic spectrum.