The effect of static electric and magnetic fields on the infrared multiphoton dissociation (IRMPD) yield of CF3D is investigated in the range 0ndash;4.3 kVthinsp;cmminus;1and 0ndash;17.3 kG. The applied static fields can induce increases in the reaction yield of up to a factor of 5 at moderate energy fluences in the essentially collision free dissociation. These enhancements in the yield are ascribed to the breakdown in the angular momentum selection rules in the electric and magnetic fields. For all cases considered, the field effects are independent of the orientation of the laser beam polarization relative to the direction of the applied electric and magnetic fields. At somewhat higher pressures, where collisions enhance the reaction yield, lower yields are observed in the 17.3 kG magnetic field than in the magnetrsquo;s residual field of about 100 G. This effect is tentatively attributed to a decrease in collisional energy transfer rates in the applied magnetic field. The measurements on the magnetic field effect are completed with some new results on the IRMPD of CF2HCl. Possible IR spectral changes induced by a 5 kVthinsp;cmminus;1field in CF3D, CF3H, and CF2HCl are investigated at a resolution of 0.06 cmminus;1.
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