Relaxation kinetics in a series of all-trans-carotenes that have excited states with different energies has been investigated using femtosecond absorption and Raman spectroscopy. The dependence on the energies shows that the (formula presented) state plays an intermediate state of the relaxation from the initially photoexcited (formula presented) state to the (formula presented) state. After the relaxation to the (formula presented) state, the excess energy is held in a (formula presented) stretching mode (formula presented) of the (formula presented) state. The lifetime of the (formula presented) mode is longer than several picoseconds in short (mini) carotenes, but it is shorter than 1 ps in long (macro) carotenes. Vibrational feature in carotenoids is of importance in energy transfer of photosynthesis, because the excess energy of the photoexcitation is stored in the (formula presented) mode during the relaxation kinetics.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2003 May 6|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics