A high resolution far infrared study of rotation in HN 3, HNCO, HNCS, and their deuterium derivatives
Abstract
The pure rotational spectra of HN 3, HNCO, HNCS and their deuterium derivatives have been obtained in the spectral range 20-250 cm -1 with spectral slit widths of 0.2-0.5 cm -1. Both the widely spaced RQK branches (Δ K = + 1) and their associated RRK and RPK branches were observed. For HN 3 the Q branches can be fitted reasonably well by first-order distortion theory, but higher-order treatment is required for HNCO and HNCS because of the unprecedentedly large centrifugal distortion. Analysis of the data yields the following values of the rotational constants A 0 - overlineB0, overlineB0 and DK respectively, all in cm -1; HN 3, 19.94 ± 0.03, 0.3967 ± 0.0002, (0.766 ± 0.002) × 10 -2; HNCO, 30.22 ± 0.1, 0.3664 ± 0.0002, 0.17 ± 0.01; HNCS, 44.70 ± 0.1, 0.1950 ± 0.001, 1.20 ± 0.1. The very large values of DK for HNCO and HNCS have significance only when taken along with terms involving K up to K10.
- Publication:
-
Journal of Molecular Spectroscopy
- Pub Date:
- September 1968
- DOI:
- 10.1016/0022-2852(68)90027-1
- Bibcode:
- 1968JMoSp..27..148K