Zircon (ZrSiO₄) mineral is a sustainable and promising material to store of radioactive waste that has received extensive attention by material, geochemical and environmental scientists. Although the incorporation of actinide elements in zircon lattices has been experimentally studied, bare fundamental work are carried out to systemically assess the structural and chemical stabilities of Pu doped zircon. The primary aim to unveil the Pu immobilization mechanism and assess the stability of Pu_xZr_1−xSiO₄ is carried out by calculating the formation energies, electron and hole affinities, and electronic levels of Pu doped zircon based on density functional theory. Our results reveal under μ = ${\mu }_{\text{O}-\text{poor}}$ condition Pu_Si⁴⁺, Pu_Zr¹⁺ and Pu_Zr⁰ are respectively energetically favorable to form with increasing the electronic chemical potential. Besides, Pu_Zr⁴⁺ is energetically favorable in an n-type environment under all these three conditions (i.e., μ = ${\mu }_{\text{O}-\text{poor}}$, μ = ${\mu }_{\text{Pu}/\text{Zr}}$, μ = ${\mu }_{\text{Pu}/\text{Si}}$). In addition, Pu doping will induce local structural distortion. Intriguingly however, self-repairing the symmetry of [ZrO₈] polyhedra is first observed via the structural distortion in Pu_Zr⁴⁺ configuration, which in turn could enhance the structural stability of Pu_xZr_1−xSiO₄. Ab initio molecular dynamic simulations demonstrate the configurations with negative formation energies are thermal stable at 500 K. The charge density difference and charge transfer are investigated to describe the chemical bonding nature. It is demonstrated Pu(5f)-O(2p) hybridization is more profound for interstitial Pu. Moreover, the bonding character of surrounding Zr atoms along [010] direction is almost identical to the pristine one, while it is distinctly changed towards [100] and [001] directions, showing remarkable anisotropy of Pu_xZr_1−xSiO₄. Oppositely, the ionicity in Pu–O bond is mainly featured when Zr or Si sites are substituted by Pu atoms which becomes stronger with increasing the hole doping process.

锆石（ZrSiO ₄）矿物是一种可持续的，有前途的材料，用于存储放射性废物，已受到材料，地球化学和环境科学家的广泛关注。尽管已通过实验研究了of系元素在锆石晶格中的掺入，但仅进行了基础研究，系统地评估了掺Pu锆石的结构和化学稳定性。通过基于密度泛函理论计算Pu掺杂锆石的形成能，电子和空穴亲和力以及电子能级，从而揭示Pu固定化机理并评估Pu _x Zr _{1- x} SiO ₄稳定性的主要目的。我们的结果表明μ= ${\mu }_{\text{Ø}-\text{较差的}}$随着电子化学势的增加，Pu _Si ⁴⁺，Pu _Zr ¹⁺和Pu _Zr ⁰分别在能量上有利于形成。此外，在所有这三个条件下，Pu _Zr ⁴⁺在n型环境中在能量上都有利（μ= ${\mu }_{\text{Ø}-\text{较差的}}$，μ= ${\mu }_{\text{普}/\text{锆}}$，μ= ${\mu }_{\text{普}/\text{硅}}$）。另外，Pu掺杂会引起局部结构变形。然而，有趣的是，首先通过Pu _Zr ⁴⁺构型的结构变形观察到[ZrO ₈ ]多面体的对称性的自我修复，这反过来又可以增强Pu _x Zr _{1- x} SiO ₄的结构稳定性。从头算分子动力学模拟表明，具有负形成能的构型在500 K下是热稳定的。研究了电荷密度差和电荷转移以描述化学键合性质。证明了Pu（5 f）-O（2 p）对于插页式Pu，杂交更为深刻。此外，沿[010]方向的周围Zr原子的键合特性几乎与原始原子相同，而沿[100]和[001]方向则明显改变，显示出Pu _x Zr _{1- x} SiO _4的显着各向异性。相反，当Zr或Si位被Pu原子取代时，Pu-O键的离子性主要表现出来，随着空穴掺杂过程的增加，Pu-O键的离子性变强。