Ion-pair dissociation dynamics of Cl2: adiabatic state correlation.

The ion-pair dissociation dynamics of Cl 2 → XUV Cl − ( S 0 1 )+ Cl + ( P 2,1 ,0 3 ) in the range 12.41−12.74 eV have been studied employing coherent extreme ultraviolet (XUV) radiation and the velocity map imaging method. The ion-pair yield spectrum has been measured, and 72 velocity map images of Cl−(1S0) have been recorded for the peaks in the spectrum. From the images, the branching ratios among the three spin−orbit components Cl+(3P2), Cl+(3P1) and Cl+(3P0) and their corresponding anisotropic parameters β have been determined. The ion-pair dissociation mechanism is explained by predissociation of Rydberg states converging to ion-core Cl2+(A2Πu). The Cl−(1S0) ion-pair yield spectrum has been assigned based on the symmetric properties of Rydberg states determined in the imaging experiments. The parallel and perpendicular transitions correspond to the excitation to two major Rydberg series, [A2Πu]3dπg,1Σu+ and [A2Πu]5sσg,1Πu, respectively. For the production of Cl+(3P0), it is found that all of them are...