Similarities in the continuous states of the group of halogenated methanes CH3X (X = Cl, Br, I): Molecular quantum defect orbital (MQDO) cross section calculations for allowed photoionization channels

Photoionization cross sections for the CH3Cl, CH3Br and CH3I molecules have been calculated with the molecular-adapted quantum defect orbital (MQDO) approach. The partial cross sections corresponding to the different Rydberg series that constitute the ionization channels of these molecules from their ground states are reported. Good agreement with experiment is found. An analysis of the results reveals that the cross section profiles are largely independent of the nature of the ligands.