Spin polarized metastable deexcitation spectroscopy as a probe of gases absorbed on metal surface
Walters, G. King
Master of Arts
Spin polarized metastable deexcitation spectroscopy provides an important surface probe, in which a beam of thermal energy metastable noble gas atoms is deexcited at the target surface under study, releasing its energy through ejection of electrons. The electrons are collected and their energy distributions measured to reveal the surface electronic structure. By spin polarizing the incoming metastable atoms and measuring the polarization of the ejected electrons, additional insight into the reaction mechanisms can be obtained. In the investigation reported in this thesis, polarized He(2$\sp3$S) atoms are used to probe a thin film of gases frozen on a cooled Cu(100) surface. The experimental results show that the reaction mechanisms occurring are similar to gas phase Penning Ionization, although some differences are apparent that can be attributed to interaction with neighboring particles and to the presence of the substrate metal surface.