First-principles calculations to investigate thermal and optical response properties of CdSe $$_{x}$$ x Te $$_{1-x}$$ 1 - x alloys

This study investigates the structural, electronic, thermal, and optical properties of the zinc blende CdSe $$_{x}$$ x Te $$_{1-x}$$ 1 - x alloy systems (where x = 0.0, 0.25, 0.50, 0.75, and 1.0 using first-principles density functional theory (DFT) calculations. To analyze the electronic structure and related properties, we employed the full-potential linear-augmented plane wave (FP-LAPW) method, utilizing the generalized gradient approximation (GGA) with the Perdew–Burke–Ernzerhof (PBE) functional and Hubbard correction (U). To understand the thermodynamical properties of these alloys, we performed quasi-harmonic lattice dynamics calculations considering phonon-phonon interactions. This approach enabled us to compute phonon group velocities, phonon lifetimes, and lattice thermal conductivity. The findings are compared with relevant previous theoretical and experimental studies, and, thus, provide valuable insights into the structural, electronic, thermal, and optical characteristics of CdSe $$_{x}$$ x Te $$_{1-x}$$ 1 - x alloys. Our study reveals that the CdSe $$_{0.5}$$ 0.5 Te $$_{0.5}$$ 0.5 ternary alloy has a potential as a better promising candidate for dual energy conversion applications by behaving as a photovoltaic as well as thermoelectric material. Graphic abstract