MOLECULAR BEAM PUMP/PROBE MICROWAVE-OPTICAL DOUBLE RESONANCE USING A LASER ABLATION SOURCE

1. S.D. Rosner, R.A. Holt and T.D. Gaily, Phys. Rev. Let. 35, 785 (1975). 2. J.E. Shirley, W.L. Barclay JR., L.M. Zuirys and T.C. Steimle, Chem. Phys. Let. 183, 363 (1991).Author Institution: Department of Chemistry, Arizona State UniversityWe have successfully obtained microwave measurement on metal containing diatomics using a pump/probe microwave-optical double resonance experiment. The technique is similar to that first used by Rosener $et. al.^{1}$ except the molecular source is a laser vaporization pulsed molecular beam rather than an effusive oven. The ablation source is of conventional design, but the beam is well colimated with a skimmer and the molecules are probed at some distance(12$^{\prime\prime}$) form the nozzle. Preliminary experiments with YF compare favorably with our previous work on this molecule using an effusive oven $source^{2}$. The signal to noise ratio is at least as good, despite the fact that the signal is observed for only 2\% of the time. Linewidths are in the range 40-230 kHz, depending on microwave power. We believe this to be the first report of this experimental technique and the versatility of the laser ablation source should allow us to record very high resolution spectra for a wide variety of molecules. Some new results for alkaline-earth triatomics will be presented