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Charge separation in photosynthesis via a spin exchange coupling mechanism

S. F. Fischer·P. O. J. Scherer
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Abstract

A new mechanism for the primary photoinduced charge separation in photosynthesis is proposed. It involves as real intermediate between the excited special pair state P* and the primary charge separated state P+HL- a trip-trip-singlet PTBLT, which consists of a triplet on the dimer P and a further triplet on the monomer BL. Both combine to a singlet. The electron transfer is caused by spin exchange couplings. The transient spectrum of the short lived intermediate, formerly taken as evidence for the charge transfer state P+BL-, is reinterpreted as a transient excitation of this trip-trip singlet.

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S. F. Fischer, P. O. J. Scherer. 1997-08-05. Charge separation in photosynthesis via a spin exchange coupling mechanism. https://arxiv.org/abs/cond-mat/9708033

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