FEBS Letters | |
An ultrafast time‐resolved anisotropy study of bacteriochlorophyll a in pyridine | |
Åkesson, Eva1  Sundström, Villy1  Martinsson, Peter1  | |
[1] Department of Chemical Physics, Lund University, P.O. Box 124, S-22100 Lund, Sweden | |
关键词: Bacteriochlorophyll a; Transient absorption anisotropy; Excited state absorption; | |
DOI : 10.1016/S0014-5793(99)01725-1 | |
学科分类:生物化学/生物物理 | |
来源: John Wiley & Sons Ltd. | |
【 摘 要 】
The transient absorption anisotropy spectrum of bacteriochlorophyll a (BChl a) in pyridine was measured in the wavelength interval 550–850 nm, 1 ps after optical excitation with a 792-nm femtosecond light pulse. In the wavelength region of Q y absorption and stimulated emission (775–825 nm), the anisotropy was found to be close to the theoretically expected value (0.4) for a two-level system. In the wavelength region 650–750 nm, where the transient absorption signal is dominated by excited state absorption, the anisotropy is reduced to ∼0.18. Anisotropy kinetics were measured at several wavelengths and found to be constant within the time window 0–5 ps, showing that no internal dynamics of the BChl a molecule change the anisotropy on the time scale of tens of picoseconds.
【 授权许可】
Unknown
【 预 览 】
Files | Size | Format | View |
---|---|---|---|
RO201912020308843ZK.pdf | 106KB | download |