First-principles study of structural and electronic properties of Al-Os intermetallic compounds

We have performed a first-principles study to evaluate the structural properties, alloying ability, elastic properties, and electronic structures of four kinds of binary Al-Os intermetallics. The structural properties of these intermetallic agree well with previously reported experimental data. The results of the formation heats indicate that the alloying ability of Al3Os2 is much stronger than Al13Os4, Al2Os and AlOs. Besides, the bulk modulus increased linearly from 72.2 to 418 GPa with increasing Os concentrations from 0 to 1. Meanwhile, our calculations revealed that most of the Al-Os alloys considered are conductors, while the Al2Os alloy is an indirect band gap semiconductor with a band gap of 0.322 eV.