The UV absorption of ClO - Part 1. The A(2)Pi-X-2 Pi spectrum at wavelengths from 285-320 nm studied by cavity ring-down spectroscopy

Citation
Wh. Howie et al., The UV absorption of ClO - Part 1. The A(2)Pi-X-2 Pi spectrum at wavelengths from 285-320 nm studied by cavity ring-down spectroscopy, PCCP PHYS C, 1(13), 1999, pp. 3079-3085
Citations number
30
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
PCCP PHYSICAL CHEMISTRY CHEMICAL PHYSICS
ISSN journal
1463-9076 → ACNP
Volume
1
Issue
13
Year of publication
1999
Pages
3079 - 3085
Database
ISI
SICI code
1463-9076(19990701)1:13<3079:TUAOC->2.0.ZU;2-K
Abstract
The UV absorption of ClO at wavelengths between 285 and 320 nm has been inv estigated using cavity ring-down spectroscopy. This wavelength region spans the (0,0) to (7,0) bands of the A (2)Pi(3/2)-X (2)Pi(3/2) and A (2)Pi(1/2) -X (2)Pi(1/2) transitions. The previously unobserved A (2)Pi(3/2)-X (2)Pi(3 /2) (0,0) and (1,0) absorption bands have been recorded with rotational res olution, and spectra of the (2,0) to (6,0) bands of the A (2)Pi(1/2)-X (2)P i(1/2) transition are shown for the first time. Analysis of the spectra giv es refined band origins and rotational constants for the A (2)Pi upsilon' l evels and reveals a strong upsilon' dependence in the linewidths of rotatio nal features. The lifetimes of the A (2)Pi(3/2) upsilon' = 0-2 and A (2)Pi( 1/2) upsilon' = 2-4 levels are revised from previous estimates, and the lif etimes of A (2)Pi(1/2) upsilon' = 5 and 6 levels have been determined. The deduced predissociation rates for A (2)Pi(3/2) upsilon' = 3-7 confirm earli er studies. The lifetimes of vibrational levels of the two spin-orbit compo nents of the A (2)Pi(Omega) state are markedly different. No evidence of J' -dependence in the predissociation is found, in contrast to the correspondi ng A (2)Pi(3/2) state of the IO radical.