Present paper reports theoretical investigation of less explored nitrides of Iridium and Osmium using semi-empirical model with charge transfer effect (CTE). This work indicates the presence of structural phase transition in these nitrides from zinc-blend (B3) to rock-salt (B1) structure on application of pressure on them. Transitions occurred at 71 GPa and 86 GPa, with sudden drops in volume of 9.54% and 8.35% in IrN and OsN. The effect of pressure on elastic properties for B3-IrN and B3-OsN is investigated for the first time. On the basis of mechanical properties, it is observed that both compounds are ductile in nature. The present study is extended to investigate transition metal alloy Ir_xOs_1-xN via Vegard’s law. To widen the applicability of our model and to explore this alloy we report structural, elastic, mechanical and thermophysical properties. The effect of pressure on Debye temperature with different concentration (x=0, 0.25, 0.5, 0.75, 1) have also been analyzed. The results are in general in good agreement with available theoretical results.

本文报道了使用具有电荷转移效应（CTE）的半经验模型对稀有铱和less氮化物进行的理论研究。这项工作表明在施加压力时，这些氮化物中存在结构相变，从锌混合（B3）到岩石盐（B1）结构。转变发生在71 GPa和86 GPa，IrN和OsN的体积突然下降了9.54％和8.35％。首次研究了压力对B3-IrN和B3-OsN弹性性能的影响。基于机械性能，观察到两种化合物本质上都是延性的。本研究扩展到研究过渡金属合金Ir _x Os _1-xN通过维加德定律。为了扩大模型的适用性并探索这种合金，我们报告了结构，弹性，机械和热物理性质。还分析了压力对不同浓度（x = 0、0.25、0.5、0.75、1）的德拜温度的影响。结果通常与可用的理论结果高度吻合。