10min:

DANIEL S. BYUN, JEFFREY J. KAY, VLADIMIR S. PETROVIC´ AND ROBERT W. FIELD, Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.

Previous work in our laboratory has shown that a single repulsive state (assigned as ^{2 +}) is responsible for predissociation of all ^{2 +} Rydberg states of CaCl in the low- n* region. The difference between the dissociation limit of CaCl and its first ionization potential is 15,500 cm^-1 while the difference is only 2,800 cm^-1 in CaF, suggesting that lower Rydberg states in CaF will not be as extensively predissociated. However, we have recently observed significant predissociation in CaF. The double resonance spectra of the low- n* ( n* =5--7) Rydberg states of CaF have been reinvestigated in an attempt to characterize the repulsive ^{2 +} state responsible for the predissociation in CaF.