Sensitive Overtone Spectroscopy of Carbonyl Sulfide between 6130 and 6650 cm−1and at 12 000 cm−1

A multipass optoacoustic cell and a color center laser have been used to record Doppler-limited overtone spectra of carbonyl sulfide in the spectral region between 6130 and 6650 cm−1. To obtain spectra around 12000 cm−1we used a phase modulation diode laser spectrometer. Eight bands of16O12C32S and two bands of16O12C34S could be detected and assigned for the first time. Comparing the spectra with the results of a global rovibrational analysis gives an agreement within 0.05 cm−1. In some cases the effect of thelresonance was calculated in a local model, in order to show its influence on the rotational energies.