Density functional theory study of phase stability and electronic properties for L12 X3Ru and XRu3 alloys

Abstract

This study employs first-principles density functional theory (DFT) to investigate the structural, mechanical, electronic, and phonon properties of L1₂-phase X₃Ru and XRu₃ alloys (X = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn). Our findings indicate that Sc₃Ru, Ti₃Ru, V₃Ru, Mn₃Ru, Zn₃Ru as well as Ru₃Ti, Ru₃V, and Ru₃Mn alloys are thermodynamically stable. All the X₃Ru and XRu₃ alloys exhibit mechanical stability, except for Ti₃Ru and Fe₃Ru. The density of states results reveal metallic behavior across all the X₃Ru and XRu₃ alloys, while charge density plots indicate metallic bonding between X and Ru, consistent with the electronic properties. Phonon dispersion curves confirm the dynamic stability in TiRu₃, VRu₃, CrRu₃, MnRu₃, FeRu₃, CoRu₃, CuRu₃, ZnRu₃ as well as in Cr₃Ru, Cu₃Ru and Co₃Ru alloys. Notably, TiRu₃, VRu₃, MnRu₃ also demonstrate thermodynamic and mechanical stability, along with higher melting temperatures compared to the widely used Ni₃Al alloy. These findings lay a theoretical foundation for further experimental investigations of X₃Ru and XRu₃ alloys, which may be promising candidates for high-temperature structural applications.

Graphical abstract