Knowledge Bank

Collisional energy transfer in optically pumped $\mathrm{<mrow\; data-mjx-texclass="ORD">13</mrow>}CH3F$ has been studied in a time resolved infrared/millimeter wave multiple resonance experiment. In this experiment a Q-switched $CO2$ laser is used to rapidly populate $J=5$ in the $v3=1$ excited vibrational state. The time evolution of the relaxation of the non-equilibrium population is then monitored via the millimeter wave probe. By appropriate selection of the rotational transition to be monitored. J changing, K changing, and v changing collisions can be studied with a minimum of theoretical deconvolution. A model has been developed to predict state-to-state population transfer rates. This model and the experimental results will be compared.