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arXiv · 0709.1832

Ground-state structure of the hydrogen double vacancy on Pd(111)

Sungho Kim·Seong-Gon Kim·S. C. Erwin
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Abstract

We determine the ground-state structure of a double vacancy in a hydrogen monolayer on the Pd(111) surface. We represent the double vacancy as a triple vacancy containing one additional hydrogen atom. The potential-energy surface for a hydrogen atom moving in the triple vacancy is obtained by density-functional theory, and the wave function of the fully quantum hydrogen atom is obtained by solving the Schrödinger equation. We find that an H atom in a divacancy defect experiences significant quantum effects, and that the ground-state wave function is centered at the hcp site rather than the fcc site normally occupied by H atoms on Pd(111). Our results agree well with scanning tunneling microscopy images.

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Sungho Kim, Seong-Gon Kim, S. C. Erwin. 2007-09-18. Ground-state structure of the hydrogen double vacancy on Pd(111). https://doi.org/10.1103/physrevb.76.214109

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