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arXiv · 1205.6374

Ab initio study of helium and hydrogen interactions in $\alpha$-Fe

C. J. Ortiz·R. Vila·J. M. Pruneda
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Abstract

Density Functional Theory (DFT) calculations show a weak interaction between hydrogen and helium in iron, in contrast to previous reports of a strong trapping of hydrogen at helium. The strong preference of He and H to occupy regions with low electronic density (such as vacancies) explains this discrepancy, with vacancy-He and vacancy-H binding forces concealing the repulsive interaction between He and H. Furthermore, Rate Theory simulations based on our DFT-calculated V$_n$He$_m$H$_p$ cluster energetics predict, as it is observed in some experiments, that synergetic effects could be expected between H and He in iron under irradiation.

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C. J. Ortiz, R. Vila, J. M. Pruneda. 2012-05-29. Ab initio study of helium and hydrogen interactions in $\alpha$-Fe. https://arxiv.org/abs/1205.6374

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