Nonlinear laser spectroscopy of CH₃F at 3.39 microns

Stark-tuned nonlinear laser spectroscopy is applied to a few transitions in CH3F near 3.39 μ, with limiting linewidths of 100 kHz being observed. Dipole moments in excited vibrational states, as well as in the ground state, have been measured. Evidence for a new perpendicular band in this region is presented. © 1972.