Rydberg states of 7Li2 by pulsed optical–optical double resonance spectroscopy: Molecular constants of 7Li2+

Three Rydberg series of electronic states of 7Li2 have been characterized by pulsed optical–optical double resonance spectroscopy. The observed Rydberg states, which include the previously reported E 1Σ+g and G 1Πg states, have been identified as 3–10sσ 1Σ+g, 3–10dσ 1Σ+g, and 3–15dπ 1Πg. The molecular constants for several of the upper members of each of the above series have been used to deduce the ionization potential of 7Li2 and molecular constants for the X 2Σg+ state of 7Li2+. The former was determined to be T0(∞)=41 496±4 cm−1. The latter were found to be in good agreement with recent ab initio calculations.