Parts | Days | Selection | Search | Updates | Downloads | Help
MO: Fachverband Molekülphysik
MO 21: Electronic Spectroscopy I
MO 21.5: Talk
Thursday, March 17, 2011, 11:30–11:45, MER 02
IR-UV double resonance spectroscopy of radicals using a free electron laser — •Kathrin Fischer1, Patrick Hemberger1, Ingo Fischer1, and Anouk Rijs2 — 1Institut für Physikalische und Theoretische Chemie, Würzburg, Germany — 2FOM Intitute for Plasma Physics, Rijnhuizen, Netherlands
A suitable technique to distinguish between isomers is IR spectroscopy, if they have different or characteristic absorption bands. When the isomer of interest is a carbene or radical, normal IR spectroscopy is not possible, because of low number density. Hence, the solution for this challenge is a free electron laser experiment, which combines IR spectroscopy with mass spectrometry. Initial experiments on the allyl radical showed that pyrolytically generated radicals can be investigated. During our measurements of trifluoromethylphenyl carbene (TFPC) we noticed that a third isomer exists in the free jet beside the singlet and triplet isomers. This isomer could be identified as trifluorostyrene and shows the greatest percentage. This result was confirmed by calculations, which revealed that the trifluorostyrene is 185 kJ mol-1 lower in energy than the carbene. [1]