Rotational distributions of excited CN molecules following electron- and photon-stimulated desorption from surfaces

Journal Article · Wed Sep 15 00:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.8222· OSTI ID:6193383

Xu, J; Barnes, A; Albridge, R; Ewig, C; Tolk, N ^[1]; Hulett, Jr, L D ^[2]

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1. Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)
2. Oak Ridge National Laboratory, P.O. Box 2008, MS 6142, Oak Ridge, Tennessee 37831-6142 (United States)

We report systematic experimental studies of rotational distributions of excited CN desorbed from alkali-metal and alkali-metal-halide surfaces following excitation by incident photons and electrons. Newly measured rotational spectra are found to exhibit temperature-independent non-Boltzmann features that are uniquely correlated to the particular alkali-metal component of the substrate. In addition, we observe that photon-excitation functions and cross sections for CN[sup *] desorption also depend strongly on the alkali-metal component of the substrate. The data reveal that rotational distributions arising from electron-stimulated desorption (ESD) and photon-stimulated desorption (PSD) are markedly different from those seen in thermal desorption and molecule-surface scattering. The marked substrate dependence of the rotational distributions indicates that molecular-rotation distributions following ESD and PSD are determined by direct electronic bond breaking and reflect the nature of the potential-energy surfaces that characterize CN--alkali-metal interactions. Utilizing the measured rotational distributions in conjunction with a hindered rotor model, we have constructed angular-dependent potential surfaces.

• OSTI ID: 6193383
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:11; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
665000* -- Physics of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALI METALS
CARBON COMPOUNDS
CARBON NITRIDES
CROSS SECTIONS
DESORPTION
ELEMENTS
ENERGY LEVELS
EXCITED STATES
METALS
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
ROTATIONAL STATES
SORPTION
SURFACES