MASS-RESOLVED MULTIPHOTON IONIZATION SPECTROSCOPY OF JET-COOLED CL-2-.1. BOUND-FREE-BOUND SPECTROSCOPY

Spectroscopic constants, obtained using two-color optical double reson ance via repulsive intermediate states, are presented for four ion-pai r states of Cl-2; ie, the E(0(g)(+)), beta(1(g)), f(0(g)(+)), and G(1( g)) states. One color excitation, also via a repulsive intermediate st ate, has been used to further extend the vibrational data for the beta (1(g)) state. The same pumping scheme has been used to extend a vibrat ional progression in the [2Pi(1/2)](c)4s;1(g) Rydberg state. The absen ce of perturbations when the [2Pi(1/2)](c)4s;1(g) Rydberg and the beta (1(g)) ion-pair states cross, together with the key role played by the intermediate C(1(u)) state in accessing both singlet and triplet fina l states, are discussed in terms of the changes in spin-orbital coupli ng schemes that are required on bond stretching.