Twin-donor systems for resonance energy transfer

Resonance energy transfer involving two identical donors and one acceptor i s modelled by quantum electrodynamical calculation. The results account for recent experimental observations of simultaneous excitation energy transfe r in the photochemistry of organic dyes. It is shown that a family of three energy transfer mechanisms has to be considered in order to describe fully the energy pooling phenomenon. The chromophore architecture has a pivotal role in determining the dominant mechanism. (C) 1999 Elsevier Science B.V. All rights reserved.