The overtone spectrum of carbonyl sulfide in the region of the ν1+4ν3 and 5ν3 bands by ICLAS-VECSEL

✍ Scribed by E. Bertseva; A. Campargue; Y. Ding; A. Fayt; A. Garnache; J.S. Roberts; D. Romanini

• Book ID: 104151764
• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 260 KB
• Volume: 219
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1016/s0022-2852(03)00011-0

✦ Synopsis

The high-resolution overtone spectrum of OCS has been recorded in the region of the m 1 þ 4m 3 and 5m 3 bands by intracavity laser absorption spectroscopy based on an optically pumped vertical external cavity surface emitting laser (VECSEL). The extremely weak m 1 þ 4m 3 band at 8954:87 cm À1 was found to be isolated. The 5m 3 band at 10080:91 cm À1 is accompanied by two weaker bands at 9933.53 and 10114:02 cm À1 assigned to the 12 0 4-00 0 0 and 04 0 4-00 0 0 bands, respectively. In addition, the 01 1 5-01 1 0 hot band was detected together with the extremely weak band heads of the R branch of the 02 0;2 5-02 0;2 0 hot bands. Finally, the 5m 3 band of the 16 O 12 C 34 S minor isotopomer, present in natural abundance in the sample, was also observed and rotationally analyzed. Effective state parameters could be retrieved by standard band-by-band rotational fitting of the line positions, leading to a typical rms of 0:006 cm À1 . The observed line positions were compared to the predictions of the global model described by Rhaibi et al. [J. Mol. Spectrosc. 191 (1998) 32-44]. In general, the agreement is excellent, close to the experimental uncertainty (0:01 cm À1 ) thus confirming the high predictive ability of this effective Hamiltonian model. Weak but significant deviations up to 0:1 cm À1 were, however, identified for two rotational levels of the highly excited 2,16 0 ,0 dark state, observed through a local interaction with the 00 0 5 state. In the case of the 16 O 12 C 34 S isotopomer, the predicted line wavenumbers of the 5m 3 band were globally overestimated by about 0:04 cm À1 . The new data have been included in the corresponding global model, leading to almost unchanged values of the molecular parameters and a statistical agreement with the experiment.