title: Evidence for Rydberg doorway states in photoion pair formation in bromomethane.
abstract: The vacuum ultraviolet laser-excited photoion-pair formation spectrum of CH 3Br has been measured under high resolution in the threshold region. The (2 + 1) and (3 + 1) resonance-enhanced multiphoton ionization spectra in the same energy region are also reported. By comparison of the spectra in this and a more extended region, resonances in the photoion-pair formation spectrum are assigned to p and f Rydberg states. It is concluded that all the structure in the photoion-pair formation spectrum near threshold can be accounted for by members of the Omega = 0 subset of Rydberg states that act as doorway states to the ion channel.
authors.affiliation: School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, Scotland. T.Ridley@ed.ac.uk
authors.forename: Trevor
authors.initials: T
authors.lastname: Ridley
authors.forename: John T
authors.initials: JT
authors.lastname: Hennessy
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Donovan
authors.forename: Kenneth P
authors.initials: KP
authors.lastname: Lawley
authors.forename: Shiliang
authors.initials: S
authors.lastname: Wang
authors.forename: Paul
authors.initials: P
authors.lastname: Brint
authors.forename: Eoin
authors.initials: E
authors.lastname: Lane