First-Principles Investigation of Electronic, Optical, and Lattice Properties of α-In2Se3
Physics of the Solid State, vol.67, no.3, pp.247-252, 2025 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 67 Issue: 3
- Publication Date: 2025
- Doi Number: 10.1134/s1063783424602297
- Journal Name: Physics of the Solid State
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, INSPEC
- Page Numbers: pp.247-252
- Keywords: In2Se3, IR and Raman active modes, phonon density of states, phonon dispersion, Raman scattering, spectroscopic ellipsometry
- Open Archive Collection: Article
- Azerbaijan State University of Economics (UNEC) Affiliated: Yes
Abstract
Abstract: This study presents a combined experimental and theoretical investigation of the electronic and vibrational properties of α-In2Se3, employing ellipsometric measurements, Raman scattering, and ab initio lattice dynamics calculations. Ellipsometric measurements and ab initio calculations demonstrate that the α‑In2Se3 crystal behaves as an indirect-bandgap semiconductor with an approximate bandgap of 1.0 eV. Analysis of the density of states, projected onto atoms, shows that the valence band maximum primarily arises from the p-states of Se atoms, with a minor contribution from the p-states of In atoms. In contrast, the conduction band minimum mainly consists of the s-states of In atoms and the p-states of Se atoms. By comparing Raman scattering results with ab initio calculations and conducting group-theoretical analysis, we identified the phonon modes of α-In2Se3. Our study confirms that the R3m symmetry is the correct space group for the α-In2Se3 phase.