Interactions of Perylene Bisimide in the One-Dimensional Channels of Zeolite L

Supramolecularly organized host guest systems have been prepared by inserting three perylene dyes with differing end substituents into the nanosized channels of zeolite L (ZL) by gas-phase adsorption under vacuum conditions. The end substituents allowed controlling the core-to-core distances of the molecules in the channels. The three perylene dyes investigated have very similar absorption and fluorescence spectra in diluted solutions, as well as fluorescence lifetimes similar to 4 us. Large ZL crystals in the size range of 1500-3000 nm in length and about 1000 nm in diameter as well as nanosized NZL crystals of about 30 nm in length and diameter were used as hosts. Different loadings have been investigated. The photophysical properties of the materials were analyzed as suspensions in refractive index matching solvents, such as toluene or ethyl benzoic acid ester; as bulk materials in glass ampules; and by means of time-, space-, and spectrally resolved single-crystal fluorescence microspectrocopy techniques. The inserted dyes can form J-aggregates if the structure of the perylene derivative allows for short distances between the electronic transition moments in an in-line arrangement. J-coupling was not seen for the molecules with substituents that keep them further apart. Aligned and stabilized J-aggregates in one-dimensional channels provide new options for preparing optical devices, where coherent exciton delocalization over nanometer-to-micrometer scales may result in efficient photonic wires. The exciton coupling can be controlled by varying the molecular tail groups.