Intermolecular dimerization within pillared, layered clay templates

Solutions of pyrene in the presence of a pillared, layered montmorillonite clay produce hybrid organic-inorganic materials with substantial molecular loading in the gallery regions between the clay layers. The results are in sharp contrast to other aromatics, such as benzene, naphthalene, or perylen e, which show minimal incorporation of the molecules into the gallery regio ns of the clay. We present evidence that the unusual affinity for pyrene to form intermolecular dimers is the reason for the high loading. Pyrene mono mers are easily introduced to the layers. Through steric hindrance, subsequ ent intermolecular dimer formation is allowed, and they are captured by the pillared, layered structure. CW and time-resolved emission spectra strongl y indicate the presence of face-to-face intermolecular dimers (excimers) wi thin the clay galleries. The combination of the ease of high molecular load ing into an inorganic, high aspect ratio template and the collective optica l properties of the organic layer may be useful as a new means to create hy brid structures.