Vibration-rotation bands and molecular constants of carbonyl sulphide

Abstract
The vibrational absorption bands of carbonyl sulphide 12 C 16 O 33 S near 5 μ have been examined using very high resolving power. Rotational fine structure has been resolved for the first time; six bands have been studied, including two associated with the isotopic species 13 C 16 O 33 S, and a rotational analysis of each has been carried out. Values have been derived for the rotational constants B and D in the different vibrational levels, and these have been compared with the results obtained from the microwave spectrum for the lower states. It has been found that the location of certain bands, and the rotational constants B are affected by Fermi resonance and Coriolis interaction, and estimates of the unperturbed values have been made.