Energetics of He and H atoms with vacancies in tungsten: First-principles approach
Energetics of He and H atoms with vacancies in tungsten: First-principles approach
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DOI：
10.1016/j.jnucmat.2008.09.017
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发表时间：
2009
影响因子：
3.1
通讯作者：
Seung-Cheol Lee;Jung-Hae Choi;June-Gunn Lee
中科院分区：
文献类型：
--
作者：
Seung-Cheol Lee;Jung-Hae Choi;June-Gunn Lee
利用密度泛函理论估计了W中He和H原子各种缺陷构型的形成能。在w中存在空位和空位团簇时，He和H原子的共存是一个特殊的考虑。单个He原子倾向于取代位，而H原子自发地结合在具有负形成能的间隙位上。当He和H彼此靠近时，它们形成间隙对，占据松弛的四面体位点。然而，当He、H和一个空位同时存在于W的单元胞内时，He占据了空位位置，则hesu - htet对被预测为能量最低的构型。当附近有空位团簇存在时，He原子占据了空位，而H原子则略微向W方向移动。
The formation energies of various defect configurations of He and H atoms in W were estimated based on the density functional theory. A special consideration was given to the coexistence of the He and H atoms at the presence of the vacancy and vacancy cluster in W. A single He atom favors a substitutional site, while a H atom spontaneously incorporates at an interstitial site with the negative formation energy. When He and H are present close to each other, they form an interstitial pair, occupying relaxed tetrahedral sites. When He, H and a vacancy coexist within a unit cell of W, however, He occupies the vacancy site then the Hesub–Htetpair is predicted to be the lowest energy configuration. At the presence of a nearby vacancy cluster, He atoms occupy the vacant space while H atoms move slightly toward W.