First-principles calculations to investigate structural, elastic and thermodynamic properties of for 312 MAX phases

In this research, the approach of FP-LAPW (full potential linearized augmented plane wave) is employed within WIEN2K for the investigations of structural, thermodynamic, elec-tronic, and mechanical properties of the V2ScSnC2 and Nb2ScSnC2 MAX-phases quaternary compounds. The V2ScSnC2 and Nb2ScSnC2 compounds exist in "a" and "b" polymorph structures. The formation energies (Eform) investigated insure that the a-polymorph is more stable than the b one. As it happens, Nb2ScSnC2 is more stable than V2ScSnC2. The Nb2-ScSnC2 has an enhanced mechanical property compared to the V2ScSnC2 compound. The elastic constants (ECs) of interested materials fulfill all the conditions of mechanical sta-bility and revealed a ductile nature. The predicted Cauchy's pressure and Poisson's ratio possess positive values signifying the ionic character of the V2ScSnC2 compound. The quaternary Nb2ScSnC2 compound exists as amalgamation of covalent and ionic bonds with a predominance of the ionic bonding character. The high melting temperature and high Debye temperature of V2ScSnC2 and Nb2ScSnC2 make them suitable for use in harsh en-vironments. Furthermore, they exhibit potential as a promising material for thermal bar-rier coatings (TBCs). Electronic structure analysis confirm the metallic character of the two interested compounds. At high temperatures and pressures the thermodynamic properties including the Cv(Heat capacity) and ƟD (Debye temperature) are explored. We deem that this study of quaternary MAX-phase compounds will bring new insight for the experi-mentalists to employ for their future applications. & COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).