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.

Department of Organic Chemistry and †Department of Inorganic Chemistry Faculty of Science Faculty of Science Charles University Prague Hlavova 2030 8 12843 Prague 2 Czech Republic

References provided by Crossref.org

Cationic Gold(II) Complexes: Experimental and Theoretical Study

Flavinium Catalysed Photooxidation: Detection and Characterization of Elusive Peroxyflavinium Intermediates

Characterized cis-FeV(O)(OH) intermediate mimics enzymatic oxidations in the gas phase