- m at . s of t ] 5 A ug 1 99 7 Charge separation in photosynthesis via a spin exchange coupling mechanism
نویسندگان
چکیده
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 + H − L a trip-trip-singlet P T B T L , which consists of a triplet on the dimer P and a further triplet on the monomer B L. 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 + B − L , is reinterpreted as a transient excitation of this trip-trip singlet.
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