THE USE OF MAGNETIC ROTATION SPECTROSCOPY TO SIMPLIFY AND PRESORT SPECTRA - AN APPLICATION TO NIH AND CEF

The application of magnetic rotation spectroscopy (MRS) to the electronic spectra of gas phase NiH and CeF is examined. Experimental results for both MRS and laser excitation spectroscopy are presented for the NiH B2-DELTA-5/2-X2-DELTA-5/2 (1,0) and 2-PHI-7/2-X2-DELTA-5/2 (0,0) bands. A comparison between these two techniques clearly illustrates the ability of MRS to simplify and presort spectra. The power of MRS originates from its specificity for low-J, DELTA-OMEGA = DELTA-J transitions and its ability, based on the sign and magnitude of the MRS effect, to partially presort rotational branches. A simple theoretical explanation of the MRS results, based on the structure of the underlying Zeeman pattern, is presented. Also, the extension of MRS to the more complicated and congested spectrum of CeF is presented. Using MRS, a previously unassigned CeF band, near 5 68 nm, has been definitively assigned as OMEGA' = 4.5 <-- OMEGA" = 3.5.