THE 2 (3)PI(G) AND 3 (3)PI(G) STATES OF LI-7(2) - OPTICAL-OPTICAL DOUBLE-RESONANCE SPECTROSCOPY AND AB-INITIO CALCULATIONS

The (2p+2p) 2 (3) Pi(g) and (2s+3p) 3 (3) Pi(g) states of Li-7(2) have been studied both experimentally and theoretically. Vibrational level s upsilon=0-41 of the 2 (3) Pi(g) state and upsilon=6-10 of the 3 (3) Pi(g) state have been observed by perturbation facilitated optical-opt ical double resonance (PFOODR) spectroscopy. Our ab initio calculation s show that the 2 (3) Pi(g) state, although dissociating into 2p+2p at omic limit, is a Rydberg state and strongly mixed with the (2s+3p) 3 ( 3) Pi(g) and (2s+3d) 4 (3) Pi(g) Rydberg states. Our theoretical calcu lations show good agreement with our experimental results. (C) 1995 Am erican Institute of Physics.