Long-lived excitonic coherence in photosynthetic proteins has become an exciting area of research because it may provide design principles for enhancing the efficiency of energy transfer in a broad range of materials. In this publication, we provide new evidence that long-lived excitonic coherence in the Fenna-Mathew-Olson pigment-protein (FMO) complex is consistent with the assumption of cross correlation in the site basis, indicating that each site shares bath fluctuations. We analyze the structure and character of the beating crosspeak between the two lowest energy excitons in two-dimensional (2D) electronic spectra of the FMO Complex. To isolate this dynamic signature, we use the two-dimensional linear prediction Z-transform as a platform for filtering coherent beating signatures within 2D spectra. By separating signals into components in frequency and decay rate representations, we are able to improve resolution and isolate specific coherences. This strategy permits analysis of the shape, position, character, and phase of these features. Simulations of the crosspeak between excitons 1 and 2 in FMO under different regimes of cross correlation verify that statistically independent site fluctuations do not account for the elongation and persistence of the dynamic crosspeak. To reproduce the experimental results, we invoke near complete correlation in the fluctuations experienced by the sites associated with excitons 1 and 2. This model contradicts ab initio quantum mechanic/molecular mechanics simulations that observe no correlation between the energies of individual sites. This contradiction suggests that a new physical model for long-lived coherence may be necessary. The data presented here details experimental results that must be reproduced for a physical model of quantum coherence in photosynthetic energy transfer.

1.
R. E.
Blankenship
,
Molecular Mechanisms of Photosynthesis
(
Wiley-Blackwell
,
New York
,
2002
).
2.
H. V.
Amerongen
,
L.
Valkunas
, and
R. V.
Grondelle
,
Photosynthetic Excitons
(
World Scientific
,
Singapore
,
2000
).
3.
A.
Ishizaki
and
G. R.
Fleming
,
Proc. Natl. Acad. Sci. U.S.A.
106
,
17255
(
2009
).
4.
P.
Rebentrost
,
M.
Mohseni
,
I.
Kassal
,
S.
Lloyd
, and
A.
Aspuru-Guzik
,
New J. Phys.
11
,
03
(
2009
).
5.
F.
Caruso
,
A. W.
Chin
,
A.
Datta
,
S. F.
Huelga
, and
M. B.
Plenio
,
Phys. Rev. A
81
,
062346
(
2010
).
6.
T. R.
Calhoun
,
N. S.
Ginsberg
,
G. S.
Schlau-Cohen
,
Y.-C.
Cheng
,
M.
Ballottari
,
R.
Bassi
, and
G. R.
Fleming
,
J. Phys. Chem. B
113
,
16291
(
2009
).
7.
E.
Collini
,
C. Y.
Wong
,
K. E.
Wilk
,
P. M. G.
Curmi
,
P.
Brumer
, and
G. D.
Scholes
,
Nature (London)
463
,
644
(
2010
).
8.
G. S.
Engel
,
T. R.
Calhoun
,
E. L.
Read
,
T.-K.
Ahn
,
T.
Mancal
,
Y.-C.
Cheng
,
R. E.
Blankenship
, and
G. R.
Fleming
,
Nature (London)
446
,
782
(
2007
).
9.
G.
Panitchayangkoon
,
D.
Hayes
,
K. A.
Fransted
,
J. R.
Caram
,
E.
Harel
,
J.
Wen
,
R. E.
Blankenship
, and
G. S.
Engel
,
Proc. Natl. Acad. Sci. U.S.A.
107
,
12766
(
2010
).
10.
H.
Lee
,
Y.-C.
Cheng
, and
G. R.
Fleming
,
Science
316
,
1462
(
2007
).
11.
E.
Collini
and
G. D.
Scholes
,
J. Phys. Chem. A
113
,
4223
(
2009
).
12.
J.
Wen
,
H.
Zhang
,
M. L.
Gross
, and
R. E.
Blankenship
,
Proc. Natl. Acad. Sci. U.S.A.
106
,
6134
(
2009
).
13.
J.
Adolphs
and
T.
Renger
,
Biophys. J.
91
,
2778
(
2006
).
14.
A.
Camara-Artigas
,
R. E.
Blankenship
, and
J. P.
Allen
,
Photosynth. Res.
75
,
49
(
2003
).
15.
D.
Hayes
,
G.
Panitchayangkoon
,
K. A.
Fransted
,
J. R.
Caram
,
J.
Wen
,
K. F.
Freed
, and
G. S.
Engel
,
New J. Phys.
12
,
065042
(
2010
).
16.
D.
Hayes
,
J.
Wen
,
G.
Panitchayangkoon
,
R. E.
Blankenship
, and
G. S.
Engel
,
Faraday Discuss.
150
,
459
(
2011
).
17.
J. R.
Caram
and
G. S.
Engel
,
Faraday Discuss.
153
,
93
(
2011
).
18.
J.
Hybl
,
A.
Albrecht
,
S.
Faeder
, and
D.
Jonas
,
Chem. Phys. Lett.
297
,
307
(
1998
).
19.
T.
Brixner
,
T. S.
Mančal
,
I. V.
Stiopkin
, and
G. R.
Fleming
,
J. Chem. Phys.
121
,
4221
(
2004
).
20.
M. L.
Cowan
,
J. P.
Ogilvie
, and
R. J. D.
Miller
,
Chem. Phys. Lett.
386
,
184
(
2004
).
21.
S.
Mukamel
,
Nonlinear Optical Spectroscopy
(
Oxford University Press
,
New York
,
1995
).
22.
T.
Brixner
,
J.
Stenger
,
H. M.
Vaswani
,
M.
Cho
,
R. E.
Blankenship
, and
G. R.
Fleming
,
Nature (London)
434
,
625
(
2005
).
23.
A. V.
Pisliakov
,
T.
Manĉal
, and
G. R.
Fleming
,
J. Chem. Phys.
124
,
234505
(
2006
).
24.
M.
Cho
,
H. M.
Vaswani
,
T.
Brixner
,
J.
Stenger
, and
G. R.
Fleming
,
J. Phys. Chem. B
109
,
10542
(
2005
).
25.
N.
Demirdoven
,
M.
Khalil
, and
A.
Tokmakoff
,
Phys. Rev. Lett.
89
,
237401
(
2002
).
26.
Y.-C.
Cheng
and
G. R.
Fleming
,
J. Phys. Chem. A
112
,
4254
(
2008
).
27.
M.
Cho
,
Two-Dimensional Optical Spectroscopy
(
CRC
,
Boca Raton, FL
,
2009
).
28.
D.
Hayes
and
G.
Engel
,
Biophys. J.
100
,
2043
(
2011
).
29.
J. A.
Davis
,
L. V.
Dao
,
M. T.
Do
,
P.
Hannaford
,
K. A.
Nugent
, and
H. M.
Quiney
,
Phys. Rev. Lett.
100
,
227401
(
2008
).
30.
N.
Ginsberg
,
J.
Davis
,
M.
Ballottari
,
Y.
Cheng
,
R.
Bassi
, and
G.
Fleming
,
Proc. Natl. Acad. Sci. U.S.A.
108
,
3841
(
2011
).
31.
G.
Schlau-Cohen
,
T.
Calhoun
,
N.
Ginsberg
,
M.
Ballottari
,
R.
Bassi
, and
G.
Fleming
,
Proc. Natl. Acad. Sci. U.S.A.
107
,
13276
(
2010
).
32.
Y.
Cheng
,
G.
Engel
, and
G.
Fleming
,
Chem. Phys.
341
,
285
(
2007
).
33.
E.
Read
,
G.
Engel
,
T.
Calhoun
,
T.
Mancal
,
T.
Ahn
,
R.
Blankenship
, and
G.
Fleming
,
Proc. Natl. Acad. Sci. U.S.A.
104
,
14203
(
2007
).
34.
E.
Collini
and
G. D.
Scholes
,
Science
323
,
369
(
2009
).
35.
J. P.
Burg
,
Geophysics
37
,
375
(
1972
).
36.
Y. P.
Lee
and
D. S.
Chen
,
Mikrochim. Acta
94
,
85
(
1988
).
37.
V.
Mandelshtam
, and
H.
Taylor
,
Phys. Rev. Lett.
78
,
3274
(
1997
).
38.
M. R.
Wall
and
D.
Neuhauser
,
J. Chem. Phys.
102
,
8011
(
1995
).
39.
J.
Tang
and
J. R.
Norris
,
J. Magn. Reson.
69
,
180
(
1986
).
40.
J.
Tang
and
J. R.
Norris
,
Chem. Phys. Lett.
131
,
252
(
1986
).
41.
J.
Tang
and
J. R.
Norris
,
J. Magn. Reson.
78
,
23
(
1988
).
42.
J.
Tang
,
C.
Lin
,
M.
Bowman
, and
J.
Norris
,
J. Magn. Reson.
62
,
167
(
1985
).
43.
A.
Savitsky
and
M.
Golay
,
Anal. Chem.
36
,
1627
(
1964
).
44.
G.
Panitchayangkoon
,
D. V.
Voronine
,
D.
Abramavicius
,
J. R.
Caram
,
N. H. C.
Lewis
,
S.
Mukamel
, and
G. S.
Engel
,
Proc. Natl. Acad. Sci. U.S.A.
108
,
20908
(
2011
).
45.
R. E.
Fenna
and
B. W.
Matthews
,
Nature (London)
258
,
573
(
1975
).
46.
C.
Olbrich
,
T.
Jansen
,
J.
Liebers
,
M.
Aghtar
,
J.
Strumpfer
,
K.
Schulten
,
J.
Knoester
, and
U.
Kleinekathofer
,
J. Phys. Chem. B
115
,
8609
(
2011
).
47.
S.
Shim
,
P.
Rebentrost
,
S.
Valleau
, and
A.
Aspuru-Guzik
,
Biophys. J.
102
,
649
(
2012
).
48.
D.
Thomas
and
F.
Michael
,
Coherent Vibrational Dynamics
(
CRC
,
Boca Raton, Fl
,
2007
), pp.
129
.
49.
S.
Luccioli
,
A.
Imparato
,
S.
Lepri
,
F.
Piazza
, and
A.
Torcini
,
Phys. Biol.
8
,
046008
(
2011
).
50.
D.
Abramavicius
and
S.
Mukamel
,
J. Chem. Phys.
133
,
064510
(
2010
).
51.
L. B.
Jackson
,
Digital Filters and Signal Processing: With MATLAB Exercises
, 3rd ed. (
Kluwer Academic
,
Norwell, MA
,
1995
).
52.
O. P.
Sievanen
,
Appl. Spectrosc.
53
,
144
(
1999
).
53.
W. H.
Press
,
S. A.
Teukolsky
,
W. T.
Vetterling
, and
B. P.
Flannery
,
Numerical Recipes in C: The Art of Scientific Computing
, 2nd ed. (
Cambridge University Press
,
New York
,
1992
).
54.
G.
Walker
,
Proc. R. Soc. London, Ser. A
131
,
518
(
1931
).
55.
S. V.
Vaseghi
,
Advanced Signal Processing and Noise Reduction
, 4th ed. (
Wiley
,
New York
,
2009
).
56.
F.
Ni
and
H. A.
Scheraga
,
J. Magn. Reson.
70
,
506
(
1986
).
You do not currently have access to this content.