Addition/Correction Cite This: J. Phys. Chem. Lett. 2018, 9, 4436−4436
pubs.acs.org/JPCL
Correction to “Quantum Coherent Excitation Energy Transfer by Carotenoids in Photosynthetic Light Harvesting” Jerome D. Roscioli, Soumen Ghosh, Amy M. LaFountain, Harry A. Frank, and Warren F. Beck* J. Phys. Chem. Lett. 2017, 8 (20), pp 5141−5147. DOI: 10.1021/acs.jpclett.7b01791
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dimensional electronic spectra (2DES) from the peridinin− chlorophyll a protein (PCP). The cross peak is identified in the 2DES spectra shown in Figure 5 at the coordinate marked D. An improved fit for the waiting time T dependence of the amplitudes of this cross peak returns a shorter lifetime for Sx of 1.7 ± 0.4 ps. The improved fit, as now plotted in the revised Figure 3d, returns a better estimate for the long-lived amplitude offset arising from the residual S1 state of peridinin. In our model, the lifetime of Sx is determined by two processes, decay of Sx via Förster energy transfer to Chl a and nonradiative decay of Sx to S1. The rate of energy transfer from peridinin to Chl a in PCP was previously determined in pump−probe measurements with 100 fs pulses to fall in the 2.3−3.2 ps range.1−6 Using this range of time constants, our revised estimate for the lifetime of Sx in PCP from the 2DES spectra places the intrinsic lifetime of Sx in the 3.6−6.5 ps range. This estimate should be compared with our previous estimate of 4.4 ps determined from heterodyne transient grating spectroscopy with 40 fs pulses.7
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e have reevaluated the rate at which the off-diagonal excited-state absorption (ESA) cross peak assigned to the localized Sx state of peridinin decays in the broad-band two-
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Figure 3. Amplitudes and fitted models for the marked cross peaks in the 2DES spectra from PCP (Figures 2 and 5) as a function of the waiting time T: (a) exciton relaxation from peridinin to Chl a (Qx or Qy (0−1)), λex = 537 nm, λdet = 625 nm; (b) quantum beating between Chl a (Qx or Qy (0−1)) and peridinin, λex = 625 nm, λdet = 570 nm; (c) quantum beating between peridinins, λex = 600 nm, λdet = 565 nm; (d) decay of the localized peridinin cross peak due to Förster energy transfer to Qy (v = 0) and nonradiative decay to the S1 state, λex = 600 nm, λdet = 624 nm. The models for (a) and (d) were obtained from linear least-squares optimization; the models for (b) and (c) were obtained from a linear-prediction, singular value decomposition (LPSVD) program. Error bars are plotted to indicate the uncertainty in the measurements, which were obtained from the average of five 2DES spectra. The model parameters are listed in the Supporting Information as Tables S1−S3. The intensity profiles for additional features in the 2DES spectra are presented as Figures S4−S10. © XXXX American Chemical Society
REFERENCES
(1) Bautista, J. A.; Hiller, R. G.; Sharples, F. P.; Gosztola, D.; Wasielewski, M.; Frank, H. A. Singlet and Triplet Energy Transfer in the Peridinin−Chlorophyll a−Protein from Amphidinium carterae. J. Phys. Chem. A 1999, 103, 2267−2273. (2) Kleima, F. J.; Hofmann, E.; Gobets, B.; van Stokkum, I. H.; van Grondelle, R.; Diederichs, K.; van Amerongen, H. Förster Excitation Energy Transfer in Peridinin-Chlorophyll-a-Protein. Biophys. J. 2000, 78, 344−353. (3) Krueger, B. P.; Lampoura, S. S.; van Stokkum, I. H.; Papagiannakis, E.; Salverda, J. M.; Gradinaru, C. C.; Rutkauskas, D.; Hiller, R. G.; van Grondelle, R. Energy Transfer in the Peridinin Chlorophyll-a Protein of Amphidinium carterae studied by Polarized Transient Absorption and Target Analysis. Biophys. J. 2001, 80, 2843−2855. (4) Lampoura, S. S.; Krueger, B. P.; van Stokkum, I. H. M.; Salverda, J. M.; Gradinaru, C. C.; Rutkauskas, D.; Hiller, R. G.; van Grondelle, R. Energy Tranfer in the Peridinin Chlorophyll a Protein of Amphidinium carterae Studied by Polarized Absorption Measurements. Int. J. Mod. Phys. B 2001, 15, 3849−3852. (5) Zigmantas, D.; Hiller, R. G.; Sundström, V.; Polı ́vka, T. Carotenoid to Chlorophyll Energy Transfer in the PeridininChlorophyll-a-Protein Complex Involves an Intramolecular Charge Transfer State. Proc. Natl. Acad. Sci. U. S. A. 2002, 99, 16760−16765. (6) van Stokkum, I. H. M.; Papagiannakis, E.; Vengris, M.; Salverda, J. M.; Polívka, T.; Zigmantas, D.; Larsen, D. S.; Lampoura, S. S.; Hiller, R. G.; van Grondelle, R. Inter-Pigment Interactions in the Peridinin Chlorophyll Protein Studied by Global and Target Analysis of Time Resolved Absorption Spectra. Chem. Phys. 2009, 357, 70−78. (7) Ghosh, S.; Bishop, M. M.; Roscioli, J. D.; LaFountain, A. M.; Frank, H. A.; Beck, W. F. Excitation Energy Transfer by Coherent and Incoherent Mechanisms in the Peridinin−Chlorophyll a Protein. J. Phys. Chem. Lett. 2017, 8, 463−469.
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DOI: 10.1021/acs.jpclett.8b02230 J. Phys. Chem. Lett. 2018, 9, 4436−4436
