title: Substituent effects on the relaxation dynamics of furan, furfural and β-furfural: a combined theoretical and experimental approach.
abstract: For the series furan, furfural and β-furfural we investigated the effect of substituents and their positioning on the photoinduced relaxation dynamics in a combined theoretical and experimental approach. Using time resolved photoelectron spectroscopy with a high intensity probe pulse, we can, for the first time, follow the whole deactivation process of furan through a two photon probe signal. Using the extended 2-electron 2-orbital model [Nenov et al., J. Chem. Phys., 2011, 135, 034304] we explain the formation of one central conical intersection and predict the influence of the aldehyde group of the derivatives on its geometry. This, as well as the relaxation mechanisms from photoexcitation to the final outcome was investigated using a variety of theoretical methods. Complete active space self consistent field was used for on-the-fly calculations while complete active space perturbation theory and coupled cluster theory were used to accurately describe critical configurations. Experiment and theory show the relaxation dynamics of furfural and β-furfural to be slowed down, and together they disclose an additional deactivation pathway, which is attributed to the nOlonepair state introduced with the aldehyde group.
authors.affiliation: Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany. Regina.de_Vivie@cup.uni-muenchen.de.
authors.forename: Sven
authors.initials: S
authors.lastname: Oesterling
authors.affiliation: Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden.
authors.forename: Oliver
authors.initials: O
authors.lastname: Schalk
authors.affiliation: Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden.
authors.forename: Ting
authors.initials: T
authors.lastname: Geng
authors.affiliation: Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Thomas
authors.affiliation: Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden.
authors.forename: Tony
authors.initials: T
authors.lastname: Hansson
authors.affiliation: Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany. Regina.de_Vivie@cup.uni-muenchen.de.
authors.forename: Regina
authors.identifier: http://orcid.org/0000-0002-7877-5979
authors.initials: R
authors.lastname: de Vivie-Riedle