Efficient Energy Transfer and Electron Transfer in an Artificial Photosynthetic Antenna−Reaction Center Complex†

Photosynthetic antenna arrays found in nature funnel photoexcited energy into the reaction center. Attempts have been made to mimic the antenna function by using artificial chromophores, porphyrins in particular, not only to better understand the energy-transfer processes but also to create light-harvesting devices. This review covers non-covalent porphyrin assemblies, for which intra-ensemble energy-transfer processes were characterized. The essence of the mechanisms of energy transfer is summarized and specific examples are reviewed with an emphasis put on the rate and mechanism of singlet-singlet energy transfer. As these examples demonstrate, non-covalent intra-ensemble energy-transfer processes have been ascribed to the Förster-type through-space mechanism in almost all cases. The exception is porphyrin dyad and pentad from our group based on amidinium-carboxylate salt bridges. Through-bond superexchange mechanism is proposed to account for the fast excited energy-transfer processes for these unique assemblies. The importance of intermolecular interactions not only in terms of the structural aspects but also in terms of the electronic aspects is highlighted for the design of supramolecular systems in which efficient energy transfer is desired.

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Quantum Requirement of Photosynthesis in the Primarily Chlorophyll d Containing Prokaryote Acaryochloris marina

Zeitschrift für Naturforschung C ◽

10.1515/znc-1997-9-1010 ◽

1997 ◽

Vol 52 (9-10) ◽

pp. 636-638 ◽

Cited By ~ 15

Author(s):

Shigetoh Miyachi ◽

Kerstin Strassdat ◽

Hideaki Miyashita ◽

Horst Senger

Keyword(s):

Energy Transfer ◽

Reaction Center ◽

Oxygen Evolution ◽

Photosynthetic Oxygen Evolution ◽

Efficient Energy Transfer ◽

Efficient Energy ◽

Quantum Requirement ◽

Acaryochloris Marina ◽

Photosynthetic Oxygen ◽

Chlorophyll D

The recently isolated and characterized unicellular photosynthetic prokaryote Acaryochloris marina (Miyashita et al., 1996) contains chlorophylls a, d , and traces of a chlorophyll c-like pigment as well as phycocyanin. a type of allophycocyanin, zeaxanthin and cx-carotene, chlorophyll d being the predominant chlorophyll component. Quantum requirement measurements of the photosynthetic oxygen evolution resulted in about 12 quanta for excitation of chlorophylls a and d and 18 for phycocyanin. The data also revealed that these pigments are involved in energy absorption for photosynthetic oxygen evolution. Energy is transferred efficiently and equally well between the chlorophylls. Light absorbed by phycocyanin which is organized in phycobiliprotein aggregates (M arquardt et al., 1997), results in a less efficient energy transfer to the reaction center chlorophylls

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Bioinspired energy conversion

Pure and Applied Chemistry ◽

10.1351/pac200577061001 ◽

2005 ◽

Vol 77 (6) ◽

pp. 1001-1008 ◽

Cited By ~ 11

Author(s):

Rodrigo E. Palacios ◽

Stephanie L. Gould ◽

Christian Herrero ◽

Michael Hambourger ◽

Alicia Brune ◽

...

Keyword(s):

Energy Transfer ◽

Excited States ◽

Chemical Potential ◽

Photosynthetic Reaction Centers ◽

Absorption Of Light ◽

Reaction Center Complex ◽

Tetrapyrrole Chromophores ◽

Artificial Photosynthetic ◽

Covalently Linked ◽

Photosynthetic Antenna

Artificial photosynthetic antenna systems have been synthesized based on carotenoid polyenes and polymer-polyenes covalently attached to tetrapyrroles. Absorption of light in the blue/green region of the spectra excites the polyenes to their S2 state, and ultrafast singlet energy transfer to the tetrapyrroles occurs when the chromophores are in partial conjugation. The additional participation of other excited states of the polyene in the energy-transfer process is a requirement for perfect antenna function. Analogs of photosynthetic reaction centers consisting of tetrapyrrole chromophores covalently linked to electron acceptors and donors have been prepared. Excitation of these constructs results in a cascade of energy transfer/electron transfer which, in selected cases, forms a final charge-separated state characterized by a giant dipole moment (>150 D), a quantum yield approaching unity, a significant fraction of the photon energy stored as chemical potential, and a lifetime sufficient for reaction with secondary electron donors and acceptors. A new antenna-reaction center complex is described in which a carotenoid moiety is located in partial conjugation with the tetrapyrrole π-system allowing fast energy transfer (<100 fs) between the chromophores. In this assembly, the energy transduction process can be initiated by light absorbed by the polyene.

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An Artificial Photosynthetic Antenna-Reaction Center Complex

Journal of the American Chemical Society ◽

10.1021/ja991255j ◽

1999 ◽

Vol 121 (37) ◽

pp. 8604-8614 ◽

Cited By ~ 180

Author(s):

Darius Kuciauskas ◽

Paul A. Liddell ◽

Su Lin ◽

Thomas E. Johnson ◽

Steven J. Weghorn ◽

...

Keyword(s):

Reaction Center ◽

Reaction Center Complex ◽

Artificial Photosynthetic ◽

Photosynthetic Antenna

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Efficient artificial light-harvesting systems based on aggregation-induced emission constructed in supramolecular gels

Soft Matter ◽

10.1039/d1sm00993a ◽

2021 ◽

Author(s):

Xinxian Ma ◽

bo qiao ◽

Jinlong Yue ◽

JingJing Yu ◽

yutao geng ◽

...

Keyword(s):

Energy Transfer ◽

Rhodamine B ◽

Fluorescent Dyes ◽

Light Harvesting ◽

Artificial Light ◽

Efficient Energy Transfer ◽

Aggregation Induced Emission ◽

Efficient Energy ◽

Harvesting Systems ◽

Acyl Hydrazone

Based on a new designed acyl hydrazone gelator (G2), we developed an efficient energy transfer supramolecular organogel in glycol with two different hydrophobic fluorescent dyes rhodamine B (RhB) and acridine...

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