OPTICAL-OPTICAL DOUBLE-RESONANCE SPECTROSCOPY OF THE 5(1)SIGMAG(-2 USING AN ULTRASENSITIVE IONIZATION DETECTOR() SHELF STATE OF NA)

Using optical-optical double resonance and an ultrasensitive ionizatio n detector, we have been able to extensively study a wide range of int ernuclear distances for the 5 (1) Sigma(g)(+) state of Na-2. Using a c ombination of spectroscopic data and the ab initio calculations, we ha ve constructed a hybrid potential which has an outer well at shelf reg ion. For this hybrid potential, there are 54 vibrational levels in the inner well (which all have been observed in this work) and 12 vibrati onal levels in the outer well (of which only the last level has been o bserved in this work). Above the potential barrier, 78 additional vibr ational levels have been observed in this work. These spectroscopic da ta represent about 99.8% of the potential well depth.