First-principals research to mechanical, electronic, thermodynamic, and optical properties of Al-Cu intermetallics

In this study, the mechanical, electronic, thermodynamic, and optical properties of Al2Cu, AlCu, and Al4Cu9 were investigated. The analysis of the elastic constant Cij revealed that Al2Cu, AlCu, and Al4Cu9 are mechanically stable. AlCu is a brittle material, while Al2Cu and Al4Cu9 are ductile materials. Electronic properties calculation revealed that three Al-Cu intermetallics are all conductors, and the bonding of three Al-Cu intermetallics exhibit covalent character. The effects of changes in temperature and pressure on heat capacity, thermal expansion coefficient, Debye temperature, and Grüneisen parameters were studied using quasi-harmonic Debye model. The optical properties of Al-Cu intermetallic compounds, including dielectric functions, reflectivity, absorption and loss function also be studied.