Long range electron transfer across $π$-conjugated systems: role of electron correlations

S. Lakshmi; Ayan Datta; Swapan K. Pati

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Long range electron transfer across $π$-conjugated systems: role of electron correlations

S. Lakshmi·Ayan Datta·Swapan K. Pati

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Abstract

We consider a prototype polyene chain: donor-$π$(bridge)-acceptor. The distance between the donor and the acceptor is varied by increasing the number of bridged atoms and rate of electron transfer, k$_{et}$ is studied for a series of different donors, D=NH$_2$, SH, OH, and a fixed acceptor, A=NO$_2$. We observe a large k$_{et}$ even at a very large D-A separation of $\sim$ 45 $Å$, unexpected from the well-known and standard theories like the Forster theory. Such a long range electron transfer is due to the strong electron-electron interactions in the bridged orbitals that result in deconfinment of electrons in donor orbitals. Calculations at various levels: semi-empirical and many-body exact, have been performed to accurately account for such correlations.

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S. Lakshmi, Ayan Datta, Swapan K. Pati. 2005-07-02. Long range electron transfer across $π$-conjugated systems: role of electron correlations. https://arxiv.org/abs/cond-mat/0507046

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