Abstract: | Measurements have been made of the frequencies of the infrared absorption lines of CO2 in the region from 1850 cm−1 to 2150 cm−1. Observations were made at various pressures and pathlengths up to a maximum of 72 meter-atmospheres. Vibration-rotation constants were obtained characterizing the transitions 111c0–000, 111d0–000, 031c0–000, 031d0–000, 200–011c0, I22c0–011c0, 122d0–011d0 for C12O2. The 111c0–000 band due to the C13O2 molecule was also measured. |