H2 dissociation at defected Cu: Preference for reaction at vacancy and
kink sites

H2 dissociation at defected Cu: Preference for reaction at vacancy and kink sites
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by Z. Sljivancanin and B. Hammer.

Phys. Rev. B **65**, 085414 (2002).

Abstract
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The dissociation of H2 at close packed Cu surfaces containing defects is
studied by means of density functional theory calculations. Reaction at
vacancy and kink sites is highly favored over reaction at flat Cu
terraces and at adatom or step sites. The energy barriers are written as
the sum of the interaction between the H2 molecular states and the
Cu(4sp) and Cu(3d) valence states. It is the Cu(4sp) term which is
responsible for the preference for the vacancy and kink sites, and the
broken Cu-Cu bridge bonds at these sites are the key to the high
reactivity.