Spectroscopical characterization of CdNe van der Waals complex in the E1(3Σ+) Rydberg state

The lowest E1(3Σ+) Rydberg state of the CdNe van der Waals complex was investigated by an optical–optical double resonance method. The A0+(3Π) and B1(3Σ+) states were used as intermediates in the excitation from the X0+(1Σ+) ground state. Bound–bound excitation spectra of the E1←A0+ transition were recorded. They constitute a first observation of CdNe in the E1 state. Spectroscopical parameters of the E1-state potential well were determined. In the excitation spectrum of the E1←B1 transition, a nodal structure of bound-free transitions was observed and elucidated by a projection of the B1-state vibrational wave-function onto the E1-state potential barrier according to the prediction of ab initio calculations.