Electronic, elastic, and thermodynamic properties of intermetallic compounds: CaNi₂, MgNi₂, and CaMgNi₄

Abstract

Intermetallic compounds have attracted widespread attention in the field of materials science due to their unique physicochemical properties. This study systematically investigates the electronic structure, elastic properties, and thermodynamic characteristics of three intermetallic compounds—CaNi₂, MgNi₂, and CaMgNi₄—using first-principles methods to evaluate their potential applications in high-temperature structural materials, energy storage, and catalysis. The results indicate that all three materials exhibit negative formation energies, suggesting their spontaneous formation and good thermodynamic stability, with MgNi₂ having the lowest formation energy and thus the highest stability. Band structure and density of states analyses reveal the metallic nature of these compounds, with anisotropic conductivity in the order of MgNi₂ > CaMgNi₄ > CaNi₂. In terms of mechanical properties, all materials have GH/BH ratios greater than 1.075, indicating good ductility, with CaNi₂ exhibiting the best ductility and CaMgNi₄ the worst. MgNi₂ shows the highest anisotropy index, implying a higher likelihood of cracking under specific loading conditions. These findings fill the knowledge gap regarding the electronic, elastic, and thermodynamic properties of the Ca-Mg-Ni system and provide a theoretical foundation for designing novel high-performance materials for efficient batteries, catalysts, and high-temperature applications.