RYDBERG STATES AND IONIZATION-POTENTIAL OF CALCIUM MONOFLUORIDE

61 vibronic states of CaF in the region 41 93045 905 cm-1 are observed by optical-optical double resonance, rovibronically assigned, and shown to belong to 37 Rydberg electronic states. These states are organized into six core-penetrating (l2), mixed-l Rydberg series, from which we obtain an improved value of the CaF ionization potential, 47 005±20 cm-1. All previously observed low Rydberg and valence states of CaF fit smoothly into these six Rydberg series, which form the complete set of l2 series. Using this information, absolute quantum defects have been determined and the series are assigned nominally (i.e., dominant l character) as d p s . © 1990 The American Physical Society.