Having synthesised the first example of a rigid acetylene-linked perylene bismuth macrocycle, scientists in Germany and Korea have made a series of these compounds with varying ring sizes and looked at their light-harvesting capabilities with regards to ring size, to establish a structure-property relationship.
They found that the larger the ring size, the slower the energy hopping. They add that the compounds have fast energy transfer capabilities compared to other artificial light-harvesting complexes such as porphyrin-based ones.
Enormous efforts have been invested into mimicking natural light-harvesting bacteria over the past two decades; investigations have focused on efficient energy transfer in particular.
Link to journal article
Excitation energy migration in covalently linked perylene bisimide macrocycles
F Schlosser et al
Chem. Sci., 2012, DOI: 10.1039/c2sc20589k