TY - JOUR
T1 - Transient grating spectroscopy in photosynthetic purple bacteria Rhodobacter sphaeroides 2.4.1
AU - Sugisaki, Mitsuru
AU - Fujiwara, Masazumi
AU - Fujii, Ritsuko
AU - Nakagawa, Katsunori
AU - Nango, Mamoru
AU - Cogdell, Richard J.
AU - Hashimoto, Hideki
N1 - Funding Information:
This work was supported in part by the Grant-in-aid from the Japanese Ministry of Education, Culture, Sports, Science, and Technology (Grant nos. 17654083, 18340091, and 18654074).
PY - 2009/12
Y1 - 2009/12
N2 - The vibronic coherence of photosynthetic pigment-protein complexes has been investigated by means of transient grating spectroscopy using sub 20 fs optical pulses. In the present work, we focus our attention on the LH2 antenna complexes from Rhodobacter sphaeroides 2.4.1 because the information about their structure investigated by the electron and atomic force microscopy is available and the electric levels of pigments are well resolved, resulting in clear absorption spectrum. The vibronic coherent oscillations with a period of a few tens of femtoseconds have been clearly observed. We found that the temporal change of the coherent oscillations reflects the vibrational relaxation in the ground state. Calculations based on the Brownian oscillator model were performed under the impulsive excitation limit. The spectral density has been determined from the Raman measurement of spheroidene. Good agreement between the calculation and the experimental results has been achieved in the linear absorption spectrum and transient grating signal, which strongly supports the validity of our model.
AB - The vibronic coherence of photosynthetic pigment-protein complexes has been investigated by means of transient grating spectroscopy using sub 20 fs optical pulses. In the present work, we focus our attention on the LH2 antenna complexes from Rhodobacter sphaeroides 2.4.1 because the information about their structure investigated by the electron and atomic force microscopy is available and the electric levels of pigments are well resolved, resulting in clear absorption spectrum. The vibronic coherent oscillations with a period of a few tens of femtoseconds have been clearly observed. We found that the temporal change of the coherent oscillations reflects the vibrational relaxation in the ground state. Calculations based on the Brownian oscillator model were performed under the impulsive excitation limit. The spectral density has been determined from the Raman measurement of spheroidene. Good agreement between the calculation and the experimental results has been achieved in the linear absorption spectrum and transient grating signal, which strongly supports the validity of our model.
KW - Carotenoid
KW - Coherent vibrational oscillations
KW - Light-harvesting antenna
KW - Photosynthesis
KW - Transient grating spectroscopy
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U2 - 10.1016/j.jlumin.2009.01.027
DO - 10.1016/j.jlumin.2009.01.027
M3 - Article
AN - SCOPUS:70349897313
VL - 129
SP - 1908
EP - 1911
JO - Journal of Luminescence
JF - Journal of Luminescence
SN - 0022-2313
IS - 12
ER -