Rotational state distributions of NH(a /sup 1/. delta. ) from HNCO photodissociation

Journal Article · Sat Aug 01 04:00:00 EDT 1987 · J. Chem. Phys.; (United States)

OSTI ID:6365877

Spiglanin, T A; Chandler, D W

We have examined the photofragmentation HNCO..-->..NH(a /sup 1/..delta..)+CO using radiation at wavelengths shorter than 230 nm. Nascent NH(a /sup 1/..delta..) shows relatively little rotational excitation, accounting for less than 12% of the energy in excess of the dissociation energy. The rotational state distributions evidence less population in high rotational states than predicted by statistical theories but more than expected on the basis of a simple impulsive dissociation. A semiclassical impulsive model that describes photoproduct rotation as developing during fragmentation successfully describes the rotational state distributions of NH(a /sup 1/..delta..) produced by HNCO photodissociation over a wide range of wavelengths. The success of this model in describing the NH rotational state distributions and previously measured CO rotational state distributions suggests that the excited state potential energy surface may be repulsive with minima in HNC and NCO bond angles each near 120/sup 0/.

• Research Organization: Combustion Research Facility, Sandia National Laboratories, Livermore, California 94550
• OSTI ID: 6365877
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 87:3; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
CARBONIC ACID DERIVATIVES
CHEMICAL REACTIONS
DECOMPOSITION
DISSOCIATION
DISTRIBUTION
ENERGY
ENERGY LEVELS
EXCITED STATES
HYDRIDES
HYDROGEN COMPOUNDS
ISOCYANIC ACID
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
ORGANIC COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
POTENTIAL ENERGY
RADICALS
ROTATIONAL STATES