First-principles study of the electronic, elastic, and optical properties of ternary LiAlTe₂

CONTEXT AND RESULTS: This study utilizes a first-principles computational approach to examine the elastic, electronic, and optical properties of LiAlTe₂, a ternary A^IB^IIIC₂^VI compound. The findings, in close agreement with experimental data, demonstrate the material's strong potential as a p-type transparent conductive material. LiAlTe₂ crystallizes in a tetragonal structure, featuring a tetrahedral arrangement that forms a stable three-dimensional framework. The material's elastic properties reveal a favorable balance between ductility and rigidity, with notable stretchability and resistance to fracture. With a direct bandgap of 2.42 eV, LiAlTe₂ exhibits a low absorption coefficient in the visible light range (< 2 × 10⁴ cm^-1), indicating high transparency. Additionally, the reduced hole effective mass of 0.82 m₀ at the valence band maximum enhances its electronic transport properties, making it an ideal candidate for applications that require high carrier mobility and transparent conductivity. COMPUTATIONAL METHODS: The calculations were carried out using density functional theory (DFT) within the Cambridge Sequential Total Energy Package (CASTEP). This study employs both GGA-PBE and PBE0 methods to analyze the material properties.