TY - JOUR
T1 - Absorption cross sections and kinetic considerations of the IO radical as determined by laser flash photolysis/laser absorption spectroscopy
AU - Stickel, R. E.
AU - Hynes, A. J.
AU - Bradshaw, J. D.
AU - Chameides, W. L.
AU - Davis, D. D.
PY - 1988
Y1 - 1988
N2 - Independent measurements of the absorption cross section of the IO radical for the A2Π-X2Π band system are reported. A value of (3.1 ± 0.6) × 10-17 cm2 was observed for the (4,0) bandhead in good agreement with an earlier investigation. Results are also reported for the (5,0), (3,0), (2,0), and (1,0) bands over the wavelength range of 410-470 nm. However, no measurable (<2 × 10-18 cm2) absorption was found for the (0,0) band. The atmospheric photodissociation rate constant, JIO, for solar zenith angles of 0°-40° was calculated to have a value of 0.06 ± 0.01 s-1. This value is a factor of 5 lower than previous estimates. Finally, the rate coefficient for the reaction IO + IO → products (3) has been measured at 760 Torr of N2 and 300 K. The measured effective bimolecular rate constant was found to be (6.6 ± 2) × 10-11 cm3·molecule-1·s-1, in good agreement with recent results by Sander (1986).
AB - Independent measurements of the absorption cross section of the IO radical for the A2Π-X2Π band system are reported. A value of (3.1 ± 0.6) × 10-17 cm2 was observed for the (4,0) bandhead in good agreement with an earlier investigation. Results are also reported for the (5,0), (3,0), (2,0), and (1,0) bands over the wavelength range of 410-470 nm. However, no measurable (<2 × 10-18 cm2) absorption was found for the (0,0) band. The atmospheric photodissociation rate constant, JIO, for solar zenith angles of 0°-40° was calculated to have a value of 0.06 ± 0.01 s-1. This value is a factor of 5 lower than previous estimates. Finally, the rate coefficient for the reaction IO + IO → products (3) has been measured at 760 Torr of N2 and 300 K. The measured effective bimolecular rate constant was found to be (6.6 ± 2) × 10-11 cm3·molecule-1·s-1, in good agreement with recent results by Sander (1986).
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U2 - 10.1021/j100318a600
DO - 10.1021/j100318a600
M3 - Article
AN - SCOPUS:0000100387
VL - 92
SP - 1862
EP - 1864
JO - Journal of Physical Chemistry
JF - Journal of Physical Chemistry
SN - 0022-3654
IS - 7
ER -