High-Fidelity RamanSpectra Simulations across Solids:Insights from GaS and GaSe, from Bulk to Layers

Gallium-based chalcogenides such as GaS and GaSe have garnered significant attention due to their unique properties and potential in optoelectronics and thin-film technologies. This study presents a detailed simulation of their Raman spectra, focusing on both bulk materials and thin layers. Using the CRYSTAL software built upon localized orbitals, we benchmark various functionals, including GGA, Meta-GGA, and hybrid ones, against experimental data. We also evaluated the performance of two distinct basis sets (TZVP and DZVP), highlighting their advantages in terms of accuracy and computational efficiency. Our work offers the first comprehensive Raman simulations for these materials, providing valuable insights for future research and a direct <i>vis-à-vis</i> with experiment.