Gas-Surface Interactions Near Dissociation Threshold
Abstract
The 365 nm photodissociation of nitrosyl chloride adsorbed on smooth MgO(100) surfaces at 90 K has been studied with mass spectrometric product detection, as well as state-selective ionization detection of NO. Results of photofragment time-of-flight (TOF) spectra of Cl and NO, state-selective detection of the NO photofragment and temperature programmed desorptions can be rationalized by a mechanism in which ClNO grows on the surface in islands with MgO defects serving as nucleation centers. No significant differences are observed between the rough and smooth surfaces, although the number of defect sites, especially oxygen vacancies, on the latter is substantially reduced. An attempt was made to determine the geometry of the adsorbates on the surface using FTIR. The results did not show any particular order, reinforcing the conclusions of clustering and lack or orientation. Preliminary attempts to dissociate ClNO by impact of hyperthermal Xe atoms led to deposition of Xe on the surface without evidence of dissociation. Collision induced dissociation (CID) of highly excited NO2 has been observed for well characterized MgO(100) surfaces with parent and product angular resolution at various internal and incident translational energies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 1994
- Accession Number
- ADA282726
Entities
People
- Curt Wittig
- Hanna Reisler
Organizations
- University of Southern California