We report a photoelectron imaging study of [Formula presented] and compare the results to [Formula presented]. Two electron-emission mechanisms are observed for the dimer anion: direct photodetachment and autodetachment, while [Formula presented] exhibits only the direct mechanism. The results provide evidence of covalent [Formula presented] coexisting with the [Formula presented] cluster anion. The autodetachment originating from the covalent species is modeled as thermionic emission transpiring in the regime of fragmentation. The bulk statistical model is found applicable to the small anion due to the availability of low-lying excited states.
ASJC Scopus subject areas
- Physics and Astronomy(all)