A bichromophore based on perylene and terrylene for energy transfer studies at the single-molecule level

A functionalized dialkylperylene and a modified terrylenetetracarboxdiimide (TTCDI) were joined together by a hexanediyl spacer. The resulting bichrom ophoric molecule 4 is a suitable model system for donor-acceptor energy tra nsfer studies at the single-molecule level. With its absorption and fluores cence maximum at shorter wavelengths (lambda(max) = 450 nm, lambda(n) = 458 nm) the dialkylperylene acts as the donor, while the TTCDI with lambda(max ) = 665 nm and lambda(fl) = 705 nm is the acceptor molecule. The synthetic route to the new bichromophoric molecule and its optical properties (UV/V i s, fluorescence spectroscopy) are presented herein. Energy transfer from th e perlyene to the terrylene moiety was confirmed by conventional ensemble f luorescence excitation and emission spectroscopy. Single bichromophores 4 e mbedded in polyvinylbutyral were imaged with a scanning confocal optical mi croscope at room temperature by selectively exciting the perylene chromopho re and detecting the terrylene emission.