ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
We report the bond selected photodissociation of HNCO from a vibrationally excited state containing three quanta of N–H stretch (3ν1) and demonstrate that initial vibrational state preparation strongly influences the photochemical branching in HNCO, producing either NCO (X 2Π) from cleavage of the N–H bond or NH (a 1Δ) from cleavage of the C–N bond. Initial excitation of the N–H dissociation coordinate by excitation of the N–H stretching overtone enhances the probability for breaking the N–H bond in the electronically excited state. Compared to isoenergetic photolysis of the ground vibrational state, photodissociation of the 3ν1 state alters the NCO quantum yield by roughly a factor of 4 at the largest photolysis energy used in this work, changing the channel that breaks the N–H bond from the minor to the major dissociation pathway. In addition, the experiment measures the quantum yields for production of NCO (ΦNCO) in the one-photon dissociation at three different photolysis wavelengths and provides a correction for the influence of photodissociation from vibrationally and rotationally excited states. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.472483
