Exciton transport in the photosynthetic unit

Abstract

In this paper we present a theoretical study of the exciton transport in the photosynthetic unit and attempt to correlate the structural and organizational properties of the unit with the exciton transport efficiency. The transport mechanism is assumed to be of the Forster type. This mechanism is shown to be equivalent to the thermally assisted exciton hopping. The transport equations are solved by the Green's function technique in a more general way than has been presented previously. We thus find it possible to study the effect of the proper R-6 coupling and random orientations of the pigment molecules. The equations are also solved for a low concentration of reaction centres when the conventional random walk picture is not valid. Various models of chlorophyll a and b mixtures are studied and by comparing their different exciton transport properties, an explanation is proposed for several observed features of the primary photochemical process. © 1978.