title: Following the relaxation dynamics of photoexcited aniline in the 273-266 nm region using time-resolved photoelectron imaging.
abstract: Time-resolved photoelectron imaging was used to investigate the relaxation dynamics of electronically excited aniline in the gas-phase following ultraviolet irradiation in the 273-266 nm region. We find that at all wavelengths studied, excitation is predominantly to the long-lived (>1 ns) S1(ππ(*)) state, which exhibits ultrafast intramolecular vibrational redistribution on a <1 ps timescale. At excitation wavelengths centred on resonant transitions in the aniline absorption spectrum that have previously been assigned to the higher lying S2(3s∕πσ(*)) state, we also see clear evidence of this state playing a role in the dynamics. However, we see no indication of any non-adiabatic coupling between the S1(ππ(*)) and S2(3s∕πσ(*)) states over the range of excitation wavelengths studied.
authors.affiliation: Institute of Photonics and Quantum Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom.
authors.forename: James O F
authors.initials: JO
authors.lastname: Thompson
authors.forename: Ruth A
authors.initials: RA
authors.lastname: Livingstone
authors.forename: Dave
authors.initials: D
authors.lastname: Townsend