Study of the electronic structures of RbCs by resonance enhanced two photon ionization (RE2PI) spectroscopy in a supersonic molecular beam

Abstract

Laser excitation spectra of the RbCs molecule are obtained by resonance enhanced two photon ionization (RE2PI) technique in a very cold pulsed molecular beam. Two progression and very anomalous peaks are observed near 650 nm. The excited electronic state that corresponds to one progression is the transition (2) $^1Π$ state already known. The other progression may correspond to the transition from the ground state to the (2) $^3∑ (0^+)$ state. Three progressions are observed near 470 nm. Two of them correspond to the (4) $^1Π$-X $^1∑^+$ and the (7) $^1∑^+$-X $^1∑^+$ transitions that have been already assigned. Possible excited electronic state that corresponds to another progression newly observed is the (6) $^1∑^+$ state.