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. 1996 Apr 30;93(9):3926–3931. doi: 10.1073/pnas.93.9.3926

Long-time quantum simulation of the primary charge separation in bacterial photosynthesis.

N Makri 1, E Sim 1, D E Makarov 1, M Topaler 1
PMCID: PMC39461  PMID: 8632991

Abstract

Accurate quantum mechanical simulations of the primary charge transfer in photosynthetic reaction centers are reported. The process is modeled by three coupled electronic states corresponding to the photoexcited chlorophyll special pair (donor), the reduced bacteriopheophytin (acceptor), and the reduced accessory chlorophyll (bridge) that interact with a dissipative medium of protein and solvent degrees of freedom. The time evolution of the excited special pair is followed over 17 ps by using a fully quantum mechanical path integral scheme. We find that a free energy of the reduced accessory chlorophyll state approximately equal to 400 cm(-1) lower than that of the excited special pair state yields state populations in agreement with experimental results on wild-type and modified reaction centers. For this energetic configuration electron transfer is a two-step process.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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