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Indexed by:期刊论文

Date of Publication:2012-10-01

Journal:JOURNAL OF NUCLEAR MATERIALS

Included Journals:SCIE、EI、Scopus

Volume:429

Issue:1-3

Page Number:216-220

ISSN No.:0022-3115

Abstract:First-principles calculations were performed to illustrate the trapping mechanism of multiple hydrogen atoms in a monovacancy of vanadium solid in terms of the stability of hydrogen-vacancy (mH-VA) complexes and H-H interactions. The preferential site for single H is not vacancy center but close to octahedral interstitial site with solution energy of -0.67 eV. Lower electron density in the presence of vacancy explains why H impurities can be easily trapped at vacancy. Among the possible mH-VA complexes, the 2H-VA conjuration is the most stable complex energetically. According to computed trapping energies, up to six H atoms can be trapped in one monovacancy inside vanadium solid. We also found that H-2 molecule is extremely difficult to survive in a small vacancy complex. The present results provide an elementary picture of the H trapping mechanism as well as H bubble formation in vanadium solid. (C) 2012 Elsevier B.V. All rights reserved.