Abstract

We perform first-principles calculations to investigate the interaction of H with He in W and Mo. One vacancy with one He atom located at the vacancy center (Vac-He1) could trap up to 12 H atoms, forming a Vac-He1–H12 complex in W and Mo. There is no H2 molecule formed in the Vac-He1–Hn (n ranges from 1 to 12) complex. The calculations of the formation energy of Vac-He1–Hn complexes indicate that Vac-He1–H4 is the most energetically favorable. The formation energy of Vac-He1–Hn is larger than that of Vac-Hn by up to 0.6eV in both W and Mo. Vac-Hem (m>1) complex could also trap H atom, and the binding energy of Vac-Hem with one closest H atom does not increase with the He atom number m. On the basis of the obtained energetics of Vac-Hem complexes, a cascade mechanism is shown that once a Vac-He1 complex traps enough H atoms, neighboring W or Mo atoms will become weakly bound thus easily removed.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.