Uranium silicides are considered to be prominent accident tolerant fuel for the light water reactors due to their high metal density and high thermal conductivity. Among the uranium silicon binary compounds, U₃Si₂ is found to be advantageous. Here, we present a systematic first principles study of electronic structure and thermophysical properties of U₃Si₂ within the framework of quasi-harmonic approximation. The relativistic effects have been treated through incorporating the spin-orbit interactions for all the calculations. The optimized cell volume from PBE method is found to be slightly underestimated, however, from the PBE+U method, it is found to be slightly overestimated as compared to the experimental volume, all the electronic structure results are comparable to the reported results. Volume dependant phonon frequencies have been calculated using the density functional perturbation theory to incorporate the effect of anharmonicity indirectly through quasi-harmonic approximation. Various thermophysical properties like free energy, thermal expansion, heat capacity, bulk modulus, etc. have been evaluated. The vibrational contribution alone to molar specific heat is found to be underestimated as compared to the experimentally reported results. Interestingly, incorporation of the electronic contribution is found to improve the results significantly. Electronic component of thermal conductivity has been calculated using the Boltzmann transport theory. The computed results are comparable to the available experimental results, which supports the reliability of the present study. All these predicted properties are very much important to gain knowledge about the U₃Si₂ based fuel.

硅化铀因其高金属密度和高导热性而被认为是轻水反应堆的主要耐事故燃料。在铀硅二元化合物中，发现U ₃ Si ₂是有利的。在这里，我们对U ₃ Si ₂的电子结构和热物理性质进行系统的第一性原理研究。在准谐波近似的框架内。通过将自旋轨道相互作用纳入所有计算中，已经对相对论效应进行了处理。通过PBE方法得到的最佳细胞体积被发现被低估了，但是，从PBE + U方法中发现，与实验体积相比，它被稍微高估了，所有的电子结构结果都可以与报道的结果相提并论。使用密度泛函微扰理论计算了体积依赖的声子频率，以通过准谐波近似间接地包含非谐波的影响。已经评估了各种热物理性质，例如自由能，热膨胀，热容，体积模量等。与实验报告的结果相比，仅对摩尔比热的振动贡献被低估了。有趣的是，发现合并电子贡献可显着改善结果。已经使用玻耳兹曼输运理论计算了热导率的电子成分。计算结果与可用的实验结果相当，这支持了本研究的可靠性。所有这些预测属性对于获得有关U的知识都非常重要 计算结果与可用的实验结果相当，这支持了本研究的可靠性。所有这些预测属性对于获得有关U的知识都非常重要 计算结果与可用的实验结果相当，这支持了本研究的可靠性。所有这些预测属性对于获得有关U的知识都非常重要₃ Si ₂基燃料。