Physics

Phase stability and electronic structure of Heusler alloys Ti$_2$VZ (Z = Al, As, Ga, Ge, In, P, Sb, Si, Sn)

A. A. Raev, K. R. Erager, V. V. Sokolovskiy, V. D. Buchel'nikov

Chelyabinsk State University, Chelyabinsk, Russian Federation

Abstract: The article deals with the chemical stability, structural, magnetic, and electronic properties of Ti$_2$VZ (Z = Al, As, Ga, Ge, In, P, Sb, Si, Sn) alloys using density functional theory methods. All compounds are found thermodynamically stable, and their stability correlates with the valence electron concentration ($e/a$) and decreases for heavier elements. The magnetic properties depend on composition and the degree of tetragonality: in the cubic phase, an increase in $e/a$ reduces magnetization intensity, whereas lattice distortion increases it. Half-metallic behavior with $100 \%$ spin polarization appears at $e/a = 4$ and $4,25$, while Ti$_2$VSb ($e/a = 4,5$) acquires a semiconducting state with a narrow gap $\sim0,1$ eV. The results agree with PBE functional calculations and demonstrate the advantages of the SCAN functional for accurate description of complex alloys.

Keywords: Heusler alloys Ti-VZ, half-metallic behavior, spin polarization, tetragonal distortion, electronic structure, magnetic properties, SCAN functional.

UDC: 538.911

Received: 06.07.2025

DOI: 10.14529/mmph250308