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Updated: Jun 23, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Structure of isolated xanthone in the T1 state obtained via combined UV/IR spectroscopy
Kristina Bartl1, Andreas Funk, Markus Gerhards
1Fachbereich Chemie and Research Center OPTIMAS, TU Kaiserslautern, Erwin-Schrödinger-Str. 52, 67663 Kaiserslautern, Germany.
Abstract:
In order to extend combined UV/IR spectroscopy to triplet states, xanthone has been chosen as a model system due to its efficient intersystem crossing (ISC). The IR/R2PI (resonant two-photon ionisation) spectrum of the electronic ground state (S(0)) as well as the IR spectrum of the T(1) state have been recorded in a supersonic jet. We show that the IR spectrum of a triplet state can be recorded subsequent to an ISC. In combination with DFT and TDDFT calculations, structural assignments are performed and geometrical changes are identified.
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