Impact of M atomic species on physical properties of M2TlC (M = Ti, Zr, Hf): A first principles calculation

We characterize the physical feature of M2TlC (M = Ti, Zr, and Hf) MAX phase ternary carbides applying density functional theory. Along with previously calculated structural, elastic, and electrical properties, Vickers hardness, dynamical stability, and optical feature of the phases are also calculated. The Pugh ratio and Poisson’s ratio show the compounds’ brittleness in conjunction with their potent directional covalent bonds and combination of ionic contributions. The metallic character of the phases is supported by the Fermi level overlap of the conduction band and valence band. The examined materials have moderate hardness, according to the Vickers hardness, with the Hf2TlC combination having the highest value of 2.60 GPa. A number of well-known phenomena are used to compute and thoroughly analyze the optical characteristics. Notably, all investigated compounds show reflectivity above 44% up to 12.0 eV energy, which is encompassed by the infrared and visible regions. The compounds could therefore be used, in practice, as a coating material to lessen solar heating.