Electron-Molecular Scattering and Photoionisation, 123 (1988)
Negative Ion Resonance Electron Scattering from Oriented, Physisorbed
|in "Electron-molecule scattering and photoionisation", eds. P.G. Burke and J.B. West (Plenum Press, New York, 1988), p. 123|
R.E. Palmer, P.J. Rous and R.F. Willis
The physisorption of diatomic molecules on a crystalline solid surface at
low temperature provides a means of orientating the molecular axis and
thus studying low energy electron scattering from an oriented molecule.
The cross-section for vibrational excitation of one monolayer of
O2 on graphite at 25 K has a peak near 9 eV electron energy.
The angular distribution of vibrationally inelastic electrons has been
measured; comparison with calculated distributions, which include
interference effects arising from multiple elastic electron scatttering
within the molecular layer, allows us to determine the orientation of the
O2 molecule on the surface and to identify the partial wave
content of the resonance. The dominant partial wave (p(pi)) is consistent
with the 2PIu compound state but not the