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采用密度泛函广义梯度近似方法计算O原子在δ-Pu金属体相中可能存在间隙位的结构和嵌入能。O原子稳定居于间隙位中心,使离其最近的一圈钚原子向外扩张。八面体间隙位最稳定,无自旋极化和自旋极化水平的嵌入能分别为-7.205 eV和-6.140 eV。四面体间隙位嵌入能相对稍大,是次稳定存在位置。通过不同扩散路径上的能量分析推测单个O原子在完美δ-Pu金属中的可能扩散路径。最可能扩散路径为相邻不同间隙位之间的交替扩散,八面体间隙到四面体间隙的扩散能垒为1.12 eV,而四面体间隙到八面体间隙的扩散能垒为2.72 eV。另外沿平行晶轴方向四面体间隙到四面体间隙交替直线扩散的能垒为6.40 eV,八面体间隙到八面体间隙交替扩散路径的势垒最高,大小为8.85 eV。
The density functional generalized gradient approximation method is used to calculate the structure and intercalation energy of O atoms in the δ-Pu metal bulk. The O atom is stable in the center of the interstitial space, expanding the nearest circle of plutonium atoms outwardly. The octahedral interstitial sites are the most stable, with no-spin polarization and spin polarization of -7.205 eV and -6.140 eV, respectively. Tetrahedron gap bit embedding can be relatively large, there is a stable position. The possible diffusion paths of single O atoms in the perfect δ-Pu metal are inferred by energy analysis on different diffusion paths. The most likely diffusion path is the alternating diffusion between adjacent interstitial spaces. The diffusion barrier for octahedral to tetrahedral gaps is 1.12 eV, and the diffusion barrier for tetrahedral to octahedral gaps is 2.72 eV. In addition, the energy barrier of alternating linear diffusion along tetrahedral interstices along the parallel crystal axis is 6.40 eV. The barrier with alternating diffusion paths from octahedral to octahedral interspaces is 8.85 eV.