Extension of microwave spectroscopy techniques to the infrared region

Abstract
High‐resolution frequency‐measuring spectroscopy techniques have been extended to the infrared region for the first time. The initial data obtained from this spectrometer are gain versus frequency for CO2 transitions. The gain line profile of the P(18) line of the 00°1 → 10°0 vibrational band of CO2 is reported between 1 and 12 Torr. The slope of the collison contribution to the linewidth is determined to be 4.46 MHz/Torr at 296°K in a mixture of 14% CO2, 17% N2, and 69% He.