Multichannel-quantum-defect-theory analysis of the Stark effect in autoionizing Rydberg states ofH2

The multichannel-quantum-defect theory (MQDT) of the Stark effect is applied to the simulation of transitions in molecular hydrogen to the autoionizing Rydberg states in the region between the ${\mathit{v}}^{+}$=1 and ${\mathit{v}}^{+}$=2 thresholds, with principal quantum numbers 13–19, for applied electric fields in the range 100–1300 V/cm. The vibrational coupling between Rydberg states belonging to different series is included for the first time in a MQDT Stark-effect calculation. The results of the calculations are compared with previously reported experimental results [Chem. Phys. Lett. 185, 199 (1991)]. The calculations not only advance the understanding of the experimental Stark spectra, but they also suggest that additional insight into zero-field interactions can be gained from a detailed understanding of the Stark effect in the hydrogen Rydberg states.