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Title: Singlet O 2 from Ultraviolet Excitation of the Quinoline-O 2 Complex
We report results from experiments with the quinoline-O2 complex, which was photodissociated using light near 312 nm. Photodissociation resulted in formation of the lowest excited state of oxygen, O2 a 1Δg, which we detected using resonance enhanced multiphoton ionization and velocity map ion imaging. The O2+ ion image allowed for a determination of the center-of-mass translational energy distribution, P(ET), following complex dissociation. We also report results of electronic structure calculations for the quinoline singlet ground state and lowest energy triplet state. From the CCSD/aug-cc-pVDZ//(U)MP2/cc-pVDZ calculations, we determined the lowest energy triplet state to have ππ* electronic character and to be 2.69 eV above the ground state. We also used electronic structure calculations to determine the geometry and binding energy for several quinoline-O2 complexes. The calculations indicated that the most strongly bound complex has a well depth of about 0.11 eV and places the O2 moiety above and approximately parallel to the quinoline ring system. By comparing the experimental P(ET) with the energy for the singlet ground state and the lowest energy triplet state, we concluded that the quinoline product was formed in the lowest energy triplet state. Finally, we found the experimental P(ET) to be in agreement with a Prior translational energy distribution, which suggests a statistical dissociation for the complex.  more » « less
Award ID(s):
2150871
PAR ID:
10503670
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Journal of Physical Chemistry A
Date Published:
Journal Name:
The Journal of Physical Chemistry A
Volume:
127
Issue:
23
ISSN:
1089-5639
Page Range / eLocation ID:
4957 to 4963
Subject(s) / Keyword(s):
singlet oxygen resonance enhanced multiphoton ionization REMPI velocity map ion imaging VMI
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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