Two-frequency excitation of NH3 under fast rotational relaxation conditions

An experimental investigation was made of the absorption of CO₂ laser radiation in the course of two-stage excitation of ammonia to the 2ν₂ state. An estimate was obtained of the vibrational–translational relaxation time of ammonia mixed with nitrogen. A considerable fraction of the ammonia molecules was excited to the 2ν₂ level. It was concluded that twostage excitation of ammonia provided a convenient method for the conversion of CO₂ laser radiation to the 16–20 μ range.