In the past decades, pyrochlores, such as Gd₂Zr₂O₇, have demonstrated great potential to immobilize nuclear wastes such as Pu, which results in the production of Pu₂Zr₂O₇. Due to the high radioactivity of Pu, it is difficult to investigate the radiation response behavior of Pu₂Zr₂O₇ and its physical properties of the damaged state experimentally. Consequently, few related data have been reported in the literature thus far. In this study, first‐principles calculations have been carried out to investigate the defect formation and its effect on the thermodynamic properties of Pu₂Zr₂O₇. It reveals that Pu_Zr antisite and O_8a interstitial defects are very easy to form in Pu₂Zr₂O₇. In particular, the O_8a interstitial defect can be formed spontaneously, while it is mechanically unstable. When vacancy, interstitial or antisite defects are formed in Pu₂Zr₂O₇, and the elastic moduli and Debye temperature are decreased. Besides, better ductility is resulted. As compared with other zirconate pyrochlores, such as Gd₂Zr₂O₇, the Pu₂Zr₂O₇ is suggested to be less resistant to radiation‐induced amorphization. This study demonstrates that the created defects due to self‐radiation from actinide decay have remarkable influences on the thermophysical properties of Pu₂Zr₂O₇.

中文翻译：

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Pu2Zr2O7烧绿石的缺陷形成及其对热力学性质的影响：第一性原理研究

在过去的几十年中，烧绿石（如Gd ₂ Zr ₂ O ₇）具有固定化核废料（如Pu）的巨大潜力，这导致了Pu ₂ Zr ₂ O _7的产生。由于Pu具有较高的放射性，因此难以通过实验研究Pu ₂ Zr ₂ O ₇的辐射响应行为及其损伤状态的物理性质。因此，迄今为止，在文献中很少报道相关数据。在这项研究中，已经进行了第一性原理计算，以研究缺陷的形成及其对Pu ₂ Zr热力学性质的影响。₂ O ₇。结果表明，在Pu ₂ Zr ₂ O ₇中很容易形成Pu _Zr反位点和O _8a间隙缺陷。特别是，O _8a间隙缺陷可以在机械上不稳定的同时自发形成。当空位时，在Pu ₂ Zr ₂ O ₇中形成间隙或反位缺陷，并且弹性模量和德拜温度降低。此外，导致更好的延展性。与其他锆酸盐烧绿石（例如Gd ₂ Zr ₂ O _7），Pu ₂ Zr ₂O ₇被认为对辐射诱导的非晶化具有较小的抵抗力。这项研究表明，act系元素衰变自辐射产生的缺陷对Pu ₂ Zr ₂ O ₇的热物理性质有显着影响。