Photodissociation of single-adsorbed molecules of cesium halogenides

摘要

A highly sensitive method for the detection of photodissociation (PD) of absorbed molecules has been developed using the surface ionization process. Spectral, temperature, and polarization dependences of the PD yield were measured in the quantum energy range of 0.6 $LS hv $LS 4eV and PD cross-sections were evaluated for single CsCl, CsBr, and CsI molecules on the surface of a graphite monolayer on iridium. The PD process, due to photoexcitation of absorbate molecules, was found to be of a one-quantum nature. The dissociation energy of single-absorbed molecules, as well as their orientation on the surface, were determined.