Photodissociation dynamics of the N[sub 3] radical

Journal Article · Sun Aug 15 04:00:00 EDT 1993 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.465224· OSTI ID:6278011

Continetti, R E; Cyr, D R; Osborn, D L; Leahy, D J; Neumark, D M ^[1]

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1. Department of Chemistry, University of California, Berkeley, California 94720 (United States) Chemical Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)

The dissociation dynamics of the [ital [tilde B]] [sup 2][Sigma][sub [ital u]][sup +] state of N[sub 3] were investigated using fast radical beam photodissociation coupled with a new coincidence wedge-and-strip-anode particle detector. With this detector, detailed photofragment kinetic energy and angular distributions can be measured as a function of excitation energy. Calibration of the detector by studies of the predissociation of the O[sub 2] [ital B] [sup 3][Sigma][sub [ital u]][sup [minus]] state is discussed. Methods of extracting the center-of-mass kinetic energy and angular distributions are presented. The photodissociation results for N[sub 3] show that from the vibrationless level of the [ital [tilde B]] [sup 2][Sigma][sub [ital u]][sup +] state in N[sub 3], both spin-allowed [N[sub 3][r arrow]N([sup 2][ital D])+N[sub 2]([sup 1][Sigma][sub [ital g]][sup +])] and spin-forbidden [N[sub 3][r arrow]N([sup 4][ital S])+N[sub 2]([sup 1][Sigma][sub [ital g]][sup +])] dissociation processes occur. Bend excitation in the [ital [tilde B]] [sup 2][Sigma][sub [ital u]][sup +] state, however, enhances the spin-allowed dissociation process considerably. The kinetic energy distributions reveal partially resolved vibrational structure in the N[sub 2] fragment, and indicate substantial rotational excitation of the N[sub 2]. This implies that bent geometries play a major role in the dissociation of the N[sub 3] [ital [tilde B]] state. Possible mechanisms for the spin-forbidden and spin-allowed dissociation channels are discussed.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6278011
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 99:4; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR DISTRIBUTION
BEAMS
CALIBRATION
CENTER-OF-MASS SYSTEM
COINCIDENCE METHODS
COUNTING TECHNIQUES
DISSOCIATION
DISTRIBUTION
ELEMENTS
ENERGY
ENERGY LEVELS
EXCITED STATES
KINETIC ENERGY
MOLECULAR BEAMS
NITROGEN
NONMETALS
OXYGEN
PREDISSOCIATION
RADICALS
RESOLUTION
VIBRATIONAL STATES