Springer Ser. Surf. Sci., 31, 21, 1993
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Electron, Photon Stimulated Desorption of Negative Ions from Oriented
Physisorbed Molecules
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| in "Desorption Induced by Electronic Transitions DIET V", eds. A.R. Burns, E.B. Stechel and D.R. Jennison (Springer Series in Surface Sciences, 31, 1993) p. 21 |
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R.J. Guest, R.A. Bennett, L.A. Silva, R.G. Sharpe, and R.E. Palmer
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we have studied electron and photon stimulated desorption of O-
from oriented O2 physisorbed on graphite. Two different
dissociation processes have been observed in electron stimulated
desorption, dissociative attachment (DA) and dipolar dissociation (DD).
Dissociative attachment is shown to be sensitive to the molecular
orientation on the surface, whereas in the case of dipolar dissociation,
the yield is less orientation dependent, a result we attribute to the
rotation of the molecule on the surface during the dissociation process.
Photo stimulated desorption of O- ions from
O2/graphite may also proceed via substrate excitation and
photoelectron impact on the adsorbate.
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