Dissociative Electron Attachment of O2: A Solid-State Effect on Potential Curve Crossing
Abstract
Previously published data on electron stimulated desorption (ESD) from condensed oxygen or oxygen solid matrices are reanalyzed. In the gas phase, the resonant state at 8.5 eV is known to dissociate predominantly into the second lowest limit. In this paper we point out that this dissociation requires a non-adiabatic curve crossing. In the condensed phase or solid matrices, this resonant state is found to dissociate adiabatically into the lowest limit as well as non-adiabatically into the second limit. Furthermore, we find that the branching ratio strongly depends on the kinetic energy of the dissociating atoms. The singlet excited oxygen atom formed upon dissociation into the second limit, is found to participate in an anion complex formation via incage recombination. According to the Wigner-Witmer correlation rule, the lowest state must dissociate adiabatically into the lowest limit. However, Belic and Hall found that the (lowest) state dissociates into the second lowest limit almost exclusively. This implies that the state must cross a curve in the dissociation terminating at the second lowest limit.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1992
- Accession Number
- ADA246331
Entities
People
- David E. Ramaker
- Hideo Sambe
Organizations
- George Washington University