Stationary absorption (broken lines) and time-resolved fluorescence spectra at a delay time of 0.1 ps (solid lines) of the -carotene homologues and lycopene. Insets show the chemical structures of the carotenoids. The solid arrows indicate the excitation energies used in each sample. The broken arrows indicate the photon energies used for kinetics traces.
Spectra of the photoinduced absorbance change in the carotenoids at a delay time of 0.1 ps (solid lines), 1.0 ps (broken lines), and 6.0 ps (dashed and dotted lines). Arrows show the energy used for analysis of the temporal responses.
Time courses of the transient absorption signals of the carotenoids. The probe photon energies are indicated by arrows in Fig. 2. The solid lines are the best fit curves using the exponential function described in the text.
(a) The relaxation rates plotted as a function of the energy gap. The broken line is the best fit to the energy gap law using Eq. (1). (b) The relaxation rates plotted as a function of the energy gap. The dashed-dotted line was calculated using Eqs. (2) and (3).
A schematic representation of the two potential surfaces where (a) and (b). , , , and in this figure, are the relative energy gap, the displacement of the potential energy minima, the activation energy and the reorganization energy between the electronic states of and , respectively.
Schematics of the possible relaxation pathways including the relative positions of the , , , and potential energy curves along the normal coordinates of the stretching mode in order of the number of conjugated double bonds .
The population dynamics of (open circles) and (closed circles) measured by time-resolved fluorescence and absorption, respectively.
Modeling of the kinetics of the carotenoids excited singlet states. The solid lines, broken lines, and dashed-dotted lines represent , , and , respectively. (a) Temporal profiles calculated using Eq. (4) with time constants of , , and and (b) temporal profiles calculated using Eq. (5) with time constants of , , and .
The time constants of the decay determined by time-resolved fluorescence spectroscopy and those of the rise and decay determined by time-resolved absorption spectroscopy.
The calculated energy gap between and and the activation energy of the relaxation to .
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