Potential superhard osmium dinitride with fluorite and pyrite structure: First-principles calculations
Potential superhard osmium dinitride with fluorite and pyrite structure: First-principles calculations
We have performed systematic first-principles calculations on dicarbide, -nitride, -oxide, and -boride of platinum and osmium with the fluorite structure. It is found that only $\mathrm{Pt}{\mathrm{N}}_{2}$, $\mathrm{Os}{\mathrm{N}}_{2}$, and $\mathrm{Os}{\mathrm{O}}_{2}$ are mechanically stable. In particular, $\mathrm{Os}{\mathrm{N}}_{2}$ has the highest bulk modulus of $360.7\phantom{\rule{0.3em}{0ex}}\mathrm{GPa}$. Both the band structure and density of states …