title: Circularly polarized luminescence in supramolecular assemblies of chiral bichromophoric perylene bisimides.
abstract: Chiral bichromophoric perylene bisimides are demonstrated as active materials of circularly polarized emission. The bichromophoric system exhibited circularly polarized luminescence with dissymmetry factors typical of that of similar organic chiral chromophoric systems in the monomeric state. Variation in solvent composition led to the formation of stably soluble helical aggregates through intermolecular interactions. A large enhancement in the dissymmetry of circularly polarized luminescence was exhibited by the aggregated structures both in the solution and solid states. The sum of excitonic couplings between the individual chromophoric units in the self-assembled state results in relatively large dissymmetry in the circularly polarized luminescence, thereby giving rise to enhanced dissymmetry factors for the aggregated structures. The spacer between chiral center and chromophoric units played a crucial role in the effective enhancement of chiroptical properties in the self-assembled structures. These materials might provide opportunities for the design of a new class of functional bichromophoric organic nanoarchitectures that can find potential applications in the field of chiroptical memory and light-emitting devices based on supramolecular electronics.
authors.affiliation: Graduate School of Materials Science, Nara Institute of Science and Technology, NAIST, 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan), Fax: (+81) 743-72-6179.
authors.forename: Jatish
authors.initials: J
authors.lastname: Kumar
authors.forename: Takuya
authors.initials: T
authors.lastname: Nakashima
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsumatori
authors.forename: Midori
authors.initials: M
authors.lastname: Mori
authors.forename: Masanobu
authors.initials: M
authors.lastname: Naito
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kawai
keywords: chirality; circular dichroism; dyes/pigments; luminescence; self-assembly