RESONANCE RAMAN SPECTRA OF EXCITED TRIPLET-STATES OF β-CAROTENE ISOMERS

The resonance Raman spectra of the electronically excited triplet-state of β-carotene, which was produced from the all-trans, 9-cis, 13-cis, and 15-cis isomers by means of flash-photolysis using a sensitizer, were recorded. They were very similar to one another. Isomerization of each isomer under the condition of Raman measurements was followed by HPLC. Isomerization from the cis isomers to the all-trans isomer was predominant. The results suggested that the isomers should have a common configuration in the lowest triplet-state.

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