title: Electronic spectra of 2- and 3-tolunitrile in the gas phase. II. Geometry changes from Franck-Condon fits of fluorescence emission spectra.
abstract: We determined the changes of the geometries of 2- and 3-tolunitrile upon excitation to the lowest excited singlet states from Franck-Condon fits of the vibronic intensities in several fluorescence emission spectra and of the rotational constant changes upon excitation. These structural changes can be connected to the altered electron distribution in the molecules and are compared to the results of ab initio calculations. We show how the torsional barriers of the methyl groups in both components are used as probe of the molecular changes upon electronic excitation.
authors.affiliation: Heinrich-Heine-Universität, Institut für Physikalische Chemie I, D-40225 Düsseldorf, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Gmerek
authors.affiliation: Heinrich-Heine-Universität, Institut für Physikalische Chemie I, D-40225 Düsseldorf, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Stuhlmann
authors.affiliation: División de Ciencias e Ingenierías, Universidad de Guanajuato, León, Guanajuato 37150, Mexico.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Álvarez-Valtierra
authors.affiliation: Department of Chemistry, University of Vermont, Burlington, Vermont 05405, USA.
authors.forename: David W
authors.initials: DW
authors.lastname: Pratt
authors.affiliation: Heinrich-Heine-Universität, Institut für Physikalische Chemie I, D-40225 Düsseldorf, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schmitt