Cr–Si binary silicides are promising advanced functional materials, which are widely used in semiconductors, thermoelectric and high temperature industries. However, the correlation between structural feature and the overall properties of Cr–Si silicides are not unclear. Here, we apply the first-principles to study the structural, mechanical, electronic and thermodynamic properties of Cr–Si silicides. The result shows that one novel Cr₂Si orthorhombic structure (Pnma) is predicted. It is found that the calculated bulk modulus of Cr–Si silicides decreases with increasing Si concentration. The calculated shear modulus and Young's modulus of Cr₃Si are larger than that of the other Cr–Si silicides because of the symmetrical Cr–Si bonds. However, Cr₂Si shows better ductility and good plasticity in comparison to the other Cr–Si silicides. Compared to the CrSi₂, these Cr–Si silicides show better electronic properties. Finally, it is found that the calculated Debye temperature (Θ_D) of Cr–Si silicides obeys the sequence of Cr₅Si₃>CrSi > Cr₃Si > Cr₂Si. Naturally, the high-temperature thermodynamic properties of Cr–Si silicides are attributed to the vibration of Si atom and Cr–Si bond. This work provides a theoretical framework for understanding the comprehensive properties of Cr–Si silicides and provides powerful guidelines for future improving the overall performances of Cr–Si silicides.

Cr-Si二元硅化物是有前途的高级功能材料，已广泛用于半导体，热电和高温行业。但是，Cr-Si硅化物的结构特征与整体性能之间的相关性尚不清楚。在这里，我们运用第一原理研究Cr-Si硅化物的结构，机械，电子和热力学性质。结果表明，可以预测一种新颖的Cr ₂ Si正交晶结构（Pnma）。研究发现，Cr-Si硅化物的体积模量随Si浓度的增加而降低。由于对称的Cr-Si键，计算出的Cr ₃ Si的剪切模量和杨氏模量大于其他Cr-Si硅化物。但是，Cr ₂与其他Cr-Si硅化物相比，Si具有更好的延展性和可塑性。与CrSi ₂相比，这些Cr-Si硅化物具有更好的电子性能。最后，发现所计算的德拜温度（Θ _d的Cr的CrSi硅化物服从序列）₅的Si ₃ >的CrSi>的Cr ₃的Si>的Cr ₂的Si。当然，Cr-Si硅化物的高温热力学性质归因于Si原子和Cr-Si键的振动。这项工作为理解Cr-Si硅化物的综合性能提供了理论框架，并为将来改善Cr-Si硅化物的整体性能提供了有力的指导。