A first-principles investigation of the structural, mechanical, dynamic, electronic, magnetic, and optical properties of Ti₂AC (A = Cd, S) MAX phase compounds

Abstract MAX phase compounds have a unique blend of ceramic and metallic properties and have been established as promising materials for device applications. In the present work, we have investigated the structural, dynamical, mechanical, electronic, magnetic, and optical properties of Ti 2 CdC and Ti 2 SC MAX phase compounds using a density functional theory approach through the Vienna Ab initio Simulation Package. The structural, dynamical, and mechanical properties of both MAX phase compounds are studied and found to be stable. Additionally, the mechanical properties reveal that both compounds have hardness and a crystalline anisotropic, bond-stretching, and brittle nature. From the analysis of elastic anisotropy calculations, it is found that Ti 2 CdC has metallic-like bonding, while Ti 2 SC has covalent-like bonding. The electronic and magnetic properties of the Ti 2 CdC and Ti 2 SC compounds are determined, and it is found that they have metallic and non-magnetic properties for the generalized gradient approximation (GGA): Perdew–Burke–Ernzerh (PBE) functional, whereas they have metallic and magnetic properties for the GGA: PBE + U functional(U is Hubbard parameter). We have explored the optical properties of the considered materials and found that they have compelling interactions with electromagnetic radiation, notable values of absorption energy, that less transparency occurred at the lower energy region, and that they have high thermal properties. Based on the major findings of the above considered materials, Ti 2 CdC and Ti 2 SC can be used in the fields of optoelectronic devices, sensors, advanced photonic devices, infrared imaging, solar thermal collectors, thermal insulation, nuclear devices, and energy dissipation devices.