Energy Transfer between Two-Dimensional Sheets: An Investigation of Chlorosome Lamella

Due to the evolutionary adaptation of photosynthetic architecture, chlorosomes are recognized as the most efficient natural light-harvesting systems. The role of the relative orientation of the two-dimensional lamella structure in the transfer process between the sheets remains unclear. To understand this, the angular dependence of the energy transfer between chlorosome-type sheets was modeled. We found that exciton energy transfer is significantly higher with antiparallel stacking. We present an analysis of the eigenstates for a smaller system, which provides the interpretation that the difference arises from interference effects between different transfer pathways between delocalized exciton states with different symmetry. Beyond chlorosomes, we propose that a similar behavior is likely for exciton transfer between other two-dimensional stacked materials and hence is interesting for future research.