Time, space, and spectrally resolved studies on J-aggregate interactions in zeolite L nanochannels

Physikalisches Institut and Center for Nanotechnology, CeNTech, University of Münster, Mendelstrasse 7, 48149 Münster, Germany.
Journal of the American Chemical Society (Impact Factor: 11.44). 08/2008; 130(33):10970-6. DOI: 10.1021/ja801178p
Source: PubMed

ABSTRACT Temporally and spectrally resolved confocal microscopy has been used to explore the behavior of pyronine intercalated zeolite L crystals at different loadings. The low pyronine loading of 0.6% exhibits photophysical behavior similar to that of the free molecule in solution, indicating molecules are isolated from each other in the crystal channels. The higher loading of 20% results in a dye gradient along the channel axis, and the presence of an additional red-shifted spectroscopic transition, with shorter lifetimes. The new band is assigned to an inline arrangement of the molecules undergoing a J-aggregate-type coupling, a process so far not observed in subnanometer channels.

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