Guanidinium organodisulfonate (GDS) hydrogen-bonded frameworks constructed from tetris-shaped ortho-substituted disulfonated stilbene derivatives display crystal architectures in which the stilbenes serve as pillars that connect opposing guanidinium sulfonate (GS) sheets in a continuously layered architecture while guiding the organization of the stilbene residues into packing motifs that produce unique optical properties. The constraints imposed by ortho-substitution result in a heretofore unreported topology of the pillars projecting from the two-dimensional GS sheet, while the dense packing of stilbene constituents, confined between the GS sheets, results in strong intermolecular electronic coupling. Stilbene 420 (2,2 ''-([1,1'-biphenyl]-4,4'-diyldi-2,1-ethenediyl)bis-benzenesulfonate) pillars pack in a face-to-face brickwork motif, producing a large bathochromic shift (similar to 100 nm) of the absorbance and emission spectra relative to stilbene 420 in methanol. The distyrylbenzenedisufonate (2,2'-((1E,1'E)-1,4-phenylenebis(ethene-2,1-diyl))dibenzenesulfonate) pillars, which pack in a face-to-face herringbone motif between the GS sheets, afford both hypsochromic and bathochromic shifts in their absorption spectrum, indicative of an unusually large Davydov splitting. The observation of both bathochromic and hypsochromic shifts can be attributed to the herringbone arrangement, in which both transitions are allowed due to the nonzero vector sum of the transition dipoles in both states. The large magnitude of the Davydov splitting reflects the strong intermolecular coupling between the chromophores, enforced by confinement in the GS framework. The newly discovered GS architectures evoke a new design rule that permits prediction of GS topologies in the case of longer tetris-shaped pillars.
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