Comprehensive Investigation of Crystallographic Architectures, Electronic Bandgap Characteristics, and Anisotropic Mechanical Properties in Ternary Tellurides KAlTe₂ and KInTe₂ Employing WIEN2k and CASTEP Computational Paradigms

A first-principles study was performed on the anisotropic ternary compounds KAlTe2 and KInTe2 using the WIEN2k and CASTEP codes to optimize their energy to the ground state. The optimized results were then compared with existing theoretical and experimental data for validation. The findings reveal that both KAlTe2 and KInTe2 exhibit both direct and indirect band gaps, depending on the chosen symmetry points during the calculations. The calculated band gaps for KAlTe2 and KInTe2 are found to be 1.68 eV and 0.931 eV, respectively. This dual band-gap behavior indicates that these materials have significant potential for applications in both thermoelectric and optical devices, where direct band gap semiconductors are particularly desirable for efficient energy conversion and light emission. Additionally, the study highlights that the bonding in these materials is characterized by a mixture of covalent and ionic interactions, contributing to their unique electronic properties. The combination of these features makes KAlTe2 and KInTe2 promising candidates for advanced material applications, particularly in fields where the manipulation of band structure and bonding characteristics is crucial for optimizing device performance. This work provides valuable insights into the fundamental properties of these materials and paves the way for further exploration in practical applications.