Accession Number:

ADA282726

Title:

Gas-Surface Interactions Near Dissociation Threshold

Descriptive Note:

Annual rept. 1 Mar 1993-30 Jun 1994

Corporate Author:

UNIVERSITY OF SOUTHERN CALIFORNIA DOWNEY

Personal Author(s):

Report Date:

1994-06-30

Pagination or Media Count:

7.0

Abstract:

The 365 nm photodissociation of nitrosyl chloride adsorbed on smooth MgO100 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 MgO100 surfaces with parent and product angular resolution at various internal and incident translational energies.

Subject Categories:

  • Inorganic Chemistry
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE