Excited state processes in individual multichromophoric systems

Abstract

Multichromophoric systems play a key role in biological systems (light harvesting antenna complexes, fluorescent proteins...) and are equally important in material science applications (e.g. light emitting devices (LED) based on conjugated polymers). Our approach to get insight in the excited state processes of such systems is to make use of dendrimers labeled with photostable perylene dyes. Dendrimers synthesis indeed allows changing the number, relative position and orientation of attached chromophores in a controlled way. In the present contribution, excited state processes such as energy hopping, singlet-singlet annihilation, singlet-triplet annihilation are identified in individual tetrachromophoric dendrimers immobilized in a polymer matrix. Similar processes are then demonstrated to occur as well in immobilized tetramers of a red fluorescent protein from a coral of the <i>Discosoma</i> genus (DsRed).