title: Infrared and Visible Photodissociation Spectra of Rhodamine Ions at 3 K in the Gas Phase.
abstract: Helium-tagging predissociation spectroscopy in the visible spectral range (He@VisPD) is shown for Rhodamine 123, Rhodamine 110, and Rhodamine 110's silver salt (silver carboxylate). It is shown that the spectra reflect single-photon absorption. The helium-tagged ions are in the ground vibrational state, and the He@VisPD spectra feature the Franck-Condon envelopes for the excitation to the first excited singlet state that agree very well with theoretical simulations. The S0 → S1 excitation energies are 2.712 ± 0.006 eV for Rhodamine 123, 2.700 ± 0.006 eV for Rhodamine 110, and 2.751 ± 0.006 eV for the silver salt of Rhodamine 110. The determined energies can be slightly blue-shifted due to the binding energy of helium. The Rhodamine ions were also characterized by helium-tagging infrared photodissociation spectroscopy. The distinctive spectral features of the individual derivatives are described and the spectra are compared to the classical solid-state IR spectra.
authors.affiliation: Department of Organic Chemistry and †Department of Inorganic Chemistry, Faculty of Science, Faculty of Science, Charles University in Prague , Hlavova 2030/8, 12843 Prague 2, Czech Republic.
authors.forename: Juraj
authors.initials: J
authors.lastname: Jašík
authors.affiliation: Department of Organic Chemistry and †Department of Inorganic Chemistry, Faculty of Science, Faculty of Science, Charles University in Prague , Hlavova 2030/8, 12843 Prague 2, Czech Republic.
authors.forename: Rafael
authors.initials: R
authors.lastname: Navrátil
authors.affiliation: Department of Organic Chemistry and †Department of Inorganic Chemistry, Faculty of Science, Faculty of Science, Charles University in Prague , Hlavova 2030/8, 12843 Prague 2, Czech Republic.
authors.forename: Ivan
authors.initials: I
authors.lastname: Němec
authors.affiliation: Department of Organic Chemistry and †Department of Inorganic Chemistry, Faculty of Science, Faculty of Science, Charles University in Prague , Hlavova 2030/8, 12843 Prague 2, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Roithová