The 6sς, 6dς, and 7dς Rydberg 1Σ+g States and Two Doubly Excited 1Σ+g States of Na2

Five highly excited 1 Σ + g states of Na 2 were observed for the first time by pulsed optical–optical double resonance (OODR) fluorescence excitation spectroscopy. Three of the five states are assigned to the 6 s ς 1 Σ + g , 6 d ς 1 Σ + g , and 7 d ς 1 Σ + g Rydberg states. The other two states are assigned to doubly excited 1 Σ + g states.