Fullerene–porphyrin architectures; photosynthetic antenna and reaction center models

Abstract

Fullerenes and porphyrins are molecular architectures ideally suited for devising integrated, multicomponent model systems to transmit and process solar energy. Implementation of C60 as a 3-dimensional electron acceptor holds great expectations on account of their small reorganization energy in electron transfer reactions and has exerted a noteworthy impact on the improvement of light-induced charge-separation. This article describes how the specific compositions of porphyrin chromophores linked to C60--yielding artificial light harvesting antenna and reaction center mimics--have been elegantly utilized to tune the electronic couplings between donor and acceptor sites and the total reorganization energy. Specifically, the effects that these parameters have on the rate, yield and lifetime of the energetic charge-separated states are considered.

Synthesis and photophysical properties of new catenated electron donor–acceptor materials with magnesium and free base porphyrins as donors and C60as the acceptor

“…Crucial for efficient EnT and ET is the spatial arrangement of the various light harvesting antennae and the photosynthetic reaction center. [1][2][3][4][5][6] To mimic the complex photosynthetic process, simpler model artificial photosynthetic systems have been investigated. 7 One approach that provides a suitable arrangement of the chromophores is the use of mechanically interlocked rotaxanes and catenanes with attached electron donors and electron acceptors.…”

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A new series of nanoscale electron donor-acceptor systems with [2]catenane architectures has been synthesized, incorporating magnesium porphyrin (MgP) or free base porphyrin (H 2 P) as electron donor and C 60 as electron acceptor, surrounding a central tetrahedral Cu(I)-1,10-phenanthroline ( phen) complex.Model catenated compounds incorporating only one or none of these photoactive moieties were also prepared. The synthesis involved the use of Sauvage's metal template protocol in combination with the 1,3-dipolar cycloaddition of azides and alkynes ("click chemistry"), as in other recent reports from our laboratories.

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“…A new series of nanoscale electron donor-acceptor systems with [2]catenane architectures has been synthesized, incorporating magnesium porphyrin (MgP) or free base porphyrin (H 2 P) as electron donor and C 60 as electron acceptor, surrounding a central tetrahedral Cu(I)-1,10-phenanthroline ( phen) complex.…”

Dynamics of the dispersion interaction in an energy transfer system

“…One of its most widely studied manifestations is the process of energy hopping between chromophores within light-harvesting complexes-both natural [1][2][3][4][5] and synthetic polymers such as dendrimers. 3,[6][7][8][9] In the latter connection we have recently reported the results of several calculations on energy flow [10][11][12] and competing two-photon processes. 13 Beyond the sphere of dendrimers, RET has been employed to determine a wide range of other polymeric properties; the 'spectroscopic ruler' has been readily utilised as a means of elucidating physical and morphological interface properties in complex polymer blends, for example.…”

Single-Molecular Quinone Pools: A Synthetic Model of Biochemical Energy Transducer

“…The most successful attempts were the studies on photoinduced electron transfer in artificial donor-acceptor molecules [7][8][9]. More recently, models of light-harvesting antenna systems [10][11][12] and oxygen evolving complexes [13][14][15][16] are actively studied. Nevertheless, there are still many other features of photosynthesis that are yet unexplored by model chemists.…”