Photodissociation dynamics of the N3 radical

• Published in: The Journal of chemical physics 1993-08, Vol.99 (4), p.2616-2631
• Main Authors: CONTINETTI, R. E, CYR, D. R, OSBORN, D. L, LEAHY, D. J, NEUMARK, D. M
• Format: Article
• Language: English
• Subjects: Atomic and molecular physics; Exact sciences and technology; Molecular properties and interactions with photons; Photon interactions with molecules; Physics
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/1.465224

The dissociation dynamics of the B̃ 2Σu+ state of N3 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 O2 B 3Σu− state is discussed. Methods of extracting the center-of-mass kinetic energy and angular distributions are presented. The photodissociation results for N3 show that from the vibrationless level of the B̃ 2Σu+ state in N3, both spin-allowed [N3→N(2D)+N2(1Σg+)] and spin-forbidden [N3→N(4S)+N2(1Σg+)] dissociation processes occur. Bend excitation in the B̃ 2Σu+ state, however, enhances the spin-allowed dissociation process considerably. The kinetic energy distributions reveal partially resolved vibrational structure in the N2 fragment, and indicate substantial rotational excitation of the N2. This implies that bent geometries play a major role in the dissociation of the N3 B̃ state. Possible mechanisms for the spin-forbidden and spin-allowed dissociation channels are discussed.