Two three-dimensional supramolecular organic frameworks, (H(2)bpdc)(0.5)(bipy)(0.5) (1) and (H(3)dpob)(bipy)center dot 3H(2)O (2), have been successfully constructed and structurally characterized (H(2)bpdc = 2,2'-biphenyldicarboxylic acid; H(3)dpob = 3-(2',3'-dicarboxylphenoxy)benzonic acid; bipy = 4,4'-bipydine). 1 is driven by C-H center dot center dot center dot pi hydrogen-bonded packing to three dimension. 2 origins form parallel-packed wavy chains and show pi-pi stacking-directed structure. After the SOFs are formed via weak noncovalent interaction, 1 and 2 show an enhancement in thermostability. The different conformations of bipy induced by weak noncovalent interactions are responsible for the huge dissimilarity of structural and luminescence behavior between them. Under the excitation of 365 nm ultraviolet light, 1 and 2 show stronger blue-white and green-white luminescent emissions in the solid state, respectively. In comparison with 2, supramolecular organic framework 1 shows superior performance in aggregation-induced emission (AIE) activity, which is explained and elaborated via the simple model from the viewpoint of planarity (Psi(r)) and rotatability (theta(r)). Moreover, stimuli-responses behaviors to mechanical force were evaluated to explore stability of AIE materials, luminescent shift (Delta lambda(em) approximate to 36 nm) was observed in 2, whereas almost no change of 1 was found. Subsequently, 1 doped poly(methyl methacrylate) film demonstrates the comparable intensity with the solid state at concentrations of 2.0, accompanied by the improvement of thermal stability.
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