Autoionization and interchannel mixing in atomic fluorine: The 2p⁴(¹S)ns,md Rydberg series

Experimental data on the spectroscopic and dynamic properties of the 2p⁴(¹S)ns,md series between the ¹D and ¹S thresholds of atomic fluorine are presented. These series are observed through their decay into the allowed 2p⁴(³P)εl and 2p⁴(¹D)εl ionization channels. The (¹S)ns ²S resonances are broad windows, and the (¹S)md²D resonances are narrow peaks in the principal 2p⁴(¹D)εl channel. The 2s2p^{6 2}S resonance is located at 20.99(1) eV and is seen to interact strongly with the nearby 2p⁴(¹S)4s ²S resonance. The resulting structure can serve as a sensitive marker for this interchannel mixing. Except for the interacting resonances, the data are found to be in satisfactory accord with eigenchannel R-matrix results for the total cross section. © 1996 The American Physical Society.