FIRST-PRINCIPLES STUDY OF THE STRUCTURAL, ELECTRONIC, AND MECHANICAL PROPERTIES OF CuNiZ (Z = Al, Ga, Sb, Sn) HALF-HEUSLER ALLOYS

In this study, a systematic investigation of the structural, electronic, and mechanical properties of CuNiZ (Z = Al, Ga, Sb, Sn) half-Heusler alloys was carried out based on density functional theory (DFT). The obtained results confirm the dynamical and mechanical stability of these alloys and provide insights into their structural symmetry and bonding nature. The electronic structure analysis revealed that CuNiZ alloys exhibit metallic behavior, while the calculated elastic moduli and Poisson's ratio characterize their mechanical strength. Furthermore, the calculations indicated the dominance of ionic bonding in these alloys and confirmed their compliance with fundamental mechanical stability criteria. The CuNiAl, CuNiSb, and CuNiSn alloys were found to be mechanically stable, with their anisotropy coefficients and other elastic parameters determined. This study demonstrates that CuNiZ half-Heusler alloys are promising candidates for functional materials. In particular, their mechanical robustness and structural properties make them potential candidates for applications in thermoelectric and spintronic devices.

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