Abstract:
A study was made of the fine structure of the excitation of the lower vibrational levels in SF6 molecules gasdynamically cooled to temperatures of the order of 30 K. A two-frequency infrared–infrared laser excitation method was employed. A continuously tunable CO2 laser was used for the first stage. At a frequency of 944.39 cm–1 a contrast absorption peak was detected, having a width of less than 0.1 cm–1 and corresponding to the A1g two-photon resonance.