Quantum defect theory of dipole-mixed Rydberg states in CaF

491 rovibronic levels of electronically highly excited CaF have been analyzed using multichannel quantum defect theory (MQDT). These levels, observed in the experiments described in the preceding paper, correspond to effective principal quantum numbers n 12-18, partial wave components l = 0-3, and vibration-rotation quantum numbers n = 1 and N = 0-14. A set of nondiagonal quantum defect matrices has been extracted from the experimental data by means of a global least-squares-fitting procedure, and is found to agree reasonably well with the theoretical quantum defect matrices calculated previously by Arif et al. J. Chem. Phys. 106, 4102 (1997) where the variational R-matrix method was used. The MQDT analysis accounts for rotational-electronic nonadiabatic decoupling of the Rydberg electron from the rotating dipolar core as well as for strong l-mixing induced by the latter. The quantum defects determined for l = 3 yield approximate values for the core dipole and quadrupole moments.