TY - JOUR
T1 - Effect of Isomerization on Excited-State Dynamics of Carotenoid Fucoxanthin
AU - Kuznetsova, Valentyna
AU - Chábera, Pavel
AU - Litvín, Radek
AU - Polívka, Tomáš
AU - Fuciman, Marcel
PY - 2017/5/4
Y1 - 2017/5/4
N2 - Ultrafast transient absorption spectroscopy and single-wavelength anisotropy measurements were used to study the effect of isomerization on the excited-state properties of fucoxanthin in polar and nonpolar solvents. The excitation wavelengths were 477 nm for all-trans-fucoxanthin, and 333 and 477 nm for cis-fucoxanthin. All transient absorption spectra of the fucoxanthin isomers in polar solvents show intramolecular charge transfer (ICT) state features, typical for carbonyl carotenoids. Global analysis of the data requires an additional fitting component, originated from the presence of blue and red forms of fucoxanthin in a polar protic solvent. Here we demonstrate that the ICT state decays faster than the S1 state, due to the significant contribution of the red form to the ICT state dynamics. The isomerization does not affect the S1 lifetime, but induces a larger difference between the S1- and ICT-state lifetimes in cis-fucoxanthin, which is likely caused by alterations of ICT coupling to either the S1 or S0 states; the S∗-state signal is more pronounced for cis-isomers in a nonpolar solvent.
AB - Ultrafast transient absorption spectroscopy and single-wavelength anisotropy measurements were used to study the effect of isomerization on the excited-state properties of fucoxanthin in polar and nonpolar solvents. The excitation wavelengths were 477 nm for all-trans-fucoxanthin, and 333 and 477 nm for cis-fucoxanthin. All transient absorption spectra of the fucoxanthin isomers in polar solvents show intramolecular charge transfer (ICT) state features, typical for carbonyl carotenoids. Global analysis of the data requires an additional fitting component, originated from the presence of blue and red forms of fucoxanthin in a polar protic solvent. Here we demonstrate that the ICT state decays faster than the S1 state, due to the significant contribution of the red form to the ICT state dynamics. The isomerization does not affect the S1 lifetime, but induces a larger difference between the S1- and ICT-state lifetimes in cis-fucoxanthin, which is likely caused by alterations of ICT coupling to either the S1 or S0 states; the S∗-state signal is more pronounced for cis-isomers in a nonpolar solvent.
UR - http://www.scopus.com/inward/record.url?scp=85020228024&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcb.7b02526
DO - 10.1021/acs.jpcb.7b02526
M3 - Article
C2 - 28382818
AN - SCOPUS:85020228024
SN - 1520-6106
VL - 121
SP - 4438
EP - 4447
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 17
ER -