Investigation of perylene photonic wires by combined single-molecule fluorescence and atomic force microscopy

Heterogeneous optical behavior of perylene polyisocyanides, which arises from different structures of the polymer backbone, is revealed by the combination of single-molecule fluorescence spectroscopy and atomic force microscopy. Short nonhelical perylene oligomers exhibit monomer-like fluorescence properties, whereas long helical perylene fiber emission arises from excimer sites after delocation of the excitation along the polymer backbone (see picture)