State-resolved study of coadsorption effects on the stimulated dissociation of NO sub 2 on Pt(111)

Journal Article · Wed May 01 04:00:00 EDT 1991 · Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA)

DOI:https://doi.org/10.1116/1.577460· OSTI ID:5813528

Burns, A R; Orlando, T M; Jennison, D R; Stechel, E B ^[1]

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1. Sandia National Laboratories, Division 1151, Albuquerque, New Mexico 87185 (US)

Stimulated surface processes, which are induced by electronic transitions, are especially sensitive to the presence of coadsorbates. We present here a detailed study of electron (5--350 eV) stimulated dissociation of chemisorbed NO{sub 2} on an O-covered Pt(111) surface, utilizing state-resolved laser resonance-ionization detection of the NO gas-phase product. Several dramatic effects on NO{sub 2} dissociation occur with increasing O atom coverage (up to {theta}{sub O}=0.75 monolayer). First there is a large ({times}26) enhancement in the specific dissociation yield. Second, there is a narrowing of the translational energy distributions. A third observation is a distinct propensity ({gt}4:1 at low {ital J}) for populating the upper ({Omega}=3/2) over the lower ({Omega}=1/2) level of the spin-orbit-split NO {sup 2}{Pi}{sub {Omega}} ground state. The enhanced yield can be understood in terms of increased lifetime(s) due to an O-induced reduction in charge transfer screening. Diminished charge transfer also reduces the vibrational and rotational excitation of the NO product. The spin-orbit propensity might arise from substrate reneutralization of NO{sup +} following Auger decay of the primary excitation.

• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5813528
• Journal Information: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA), Journal Name: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA) Vol. 9:3; ISSN JVTAD; ISSN 0734-2101
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ADSORPTION
CHALCOGENIDES
CHARGE EXCHANGE
DISSOCIATION
ELEMENTS
METALS
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
PLATINUM
PLATINUM METALS
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
TRANSITION ELEMENTS