title: Energy transfer within self-assembled cyclic multichromophoric arrays based on orthogonally arranged donor-acceptor building blocks.
abstract: We herein present the coordination-driven supramolecular synthesis and photophysics of a [4+4] and a [2+2] assembly, built up by alternately collocated donor-acceptor chromophoric building blocks based, respectively, on the boron dipyrromethane (Bodipy) and perylene bisimide dye (PBI). In these multichromophoric scaffolds, the intensely absorbing/emitting dipoles of the Bodipy subunit are, by construction, cyclically arranged at the corners and aligned perpendicular to the plane formed by the closed polygonal chain comprising the PBI units. Steady-state and fs time-resolved spectroscopy reveal the presence of efficient energy transfer from the vertices (Bodipys) to the edges (PBIs) of the polygons. Fast excitation energy hopping - leading to a rapid excited state equilibrium among the low energy perylene-bisimide chromophores - is revealed by fluorescence anisotropy decays. The dynamics of electronic excitation energy hopping between the PBI subunits was approximated on the basis of a theoretical model within the framework of Förster energy transfer theory. All energy-transfer processes are quantitatively describable with Förster theory. The influence of structural deformations and orientational fluctuations of the dipoles in certain kinetic schemes is discussed.
authors.affiliation: NCSR "Demokritos", Institute of Nanosciences and Nanotechnology (INN), 153 10 Athens, Greece. pistolis@chem.demokritos.gr.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Karakostas
authors.affiliation: NCSR "Demokritos", Institute of Nanosciences and Nanotechnology (INN), 153 10 Athens, Greece. pistolis@chem.demokritos.gr.
authors.forename: Antonia
authors.initials: A
authors.lastname: Kaloudi-Chantzea
authors.affiliation: NCSR "Demokritos", Institute of Nanosciences and Nanotechnology (INN), 153 10 Athens, Greece. pistolis@chem.demokritos.gr.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Martinou
authors.affiliation: Department of Physics, University of Patras, 26500 Patras, Greece.
authors.forename: Kostas
authors.initials: K
authors.lastname: Seintis
authors.affiliation: Institute of Legal Medicine and Core Facility Metabolomics, Innsbruck Medical University, Müllerstraße 44, 6020 Innsbruck, Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Pitterl
authors.affiliation: Institute of Legal Medicine and Core Facility Metabolomics, Innsbruck Medical University, Müllerstraße 44, 6020 Innsbruck, Austria.
authors.forename: Herbert
authors.initials: H
authors.lastname: Oberacher
authors.affiliation: Department of Physics, University of Patras, 26500 Patras, Greece.
authors.forename: Mihalis
authors.initials: M
authors.lastname: Fakis
authors.affiliation: Department of Chemistry, University of Patras, 26500 Patras, Greece.
authors.forename: Joannis K
authors.initials: JK
authors.lastname: Kallitsis
authors.affiliation: NCSR "Demokritos", Institute of Nanosciences and Nanotechnology (INN), 153 10 Athens, Greece. pistolis@chem.demokritos.gr.
authors.forename: George
authors.initials: G
authors.lastname: Pistolis
mesh_terms: D005025:Ethylene Dichlorides / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D007094:Imides / Q000737:chemistry; D047028:Macrocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D010569:Perylene / Q000031:analogs & derivatives / Q000737:chemistry
chemical_list: D005025:Ethylene Dichlorides; D005456:Fluorescent Dyes; D007094:Imides; D047028:Macrocyclic Compounds; C510697:perylene bisimide; D010569:Perylene