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Aggregation-induced emission (AIE) properties have been widely investigated not only because they thoroughly circumvent the notorious aggregation-caused quenching effect encountered in conventional fluorophores but also due to their promising applications in organic light-emitting diodes, fluorescent sensors and bioimaging. In this work, we reported a study of the molecular packing and luminescence properties of AIE active positional isomers (m-BPCDM and p-BPCDM) with carbazole and dicyanovinyl groups. The compound m-BPCDM based on meta-substitution showed more evident AIE processes than the compound p-BPCDM based on para-substitution, which can be attributed to the strong π–π stacking effect brought by the spatial structure of p-BPCDM. Moreover, the two positional isomers also exhibited distinct mechanochromic luminescence properties.

Three open frameworks, [Ni(pnta)2]·1.3DMF (1), [Zn2(pnta)3(OH)]·2DMF (2), and [Cd(pnta)2]·3.8DMF (3), were obtained by solvothermal reactions between 6-(pyridin-4-yl)nicotinic acid (Hpnta) and nickel(II), zinc(II) and cadmium(II) nitrate, respectively. Compound 1 is a chiral framework with a fourfold interpenetrated diamondoid network structure and two types of chiral channels. Compound 2 also possesses the fourfold interpenetrated adamantanoid architecture with helical rhombic nanotube-like channels, each of which has two sides of double-layer walls and two other sides of single-layer walls. Compound 3 is a rarely reported double-walled framework with bcu topology. The luminescent properties of compounds 2 and 3 have been studied in the solid state at room temperature.

Five new three/two-fold interpenetrated coordination polymers, namely, [Cd(mfda)(L1)] (1), [Cd(efda)(L1)] (2), [Zn2(mfda)2(L2)]·DMF·H2O (3), [Zn2(efda)2(L2)]·(DMF)0.25, (4) and [Cd2(mfda)2(L2)2]·DMF·H2O (5) (H2mfda = 9,9-dimethylfluorene-2,7-dicarboxylic acid, H2efda = 9,9-diethylfluorene-2,7-dicarboxylic acid, L1 = Methylene bis(3,5-dimethylpyrazole) and L2 = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), have been synthesized under solvent-thermal conditions with mixed ligands. Compounds 1 and 2 are isostructural and possess two-dimensional (6, 3) layered structures containing two kinds of rings. Three equivalent (6, 3) net interpenetrate in a parallel fashion to form an unprecedented mat-like 2D sheet. Compounds 3 and 4 are almost identical in structure and display threefold interpenetrating α–Po net structures. Compound 5 displays a twofold interpenetrated 3D 6-connected net with α–Po topology. The luminescent properties of these compounds have been studied in the solid state at room temperature.

Three three-dimensional coordination polymers, namely, [NH2(CH3)2][Co2(MDIP)(OH)(H2O)]·C3H7NO·H2O (1), [NH2(CH3)2]2[Mn3(MDIP)2]·2C3H7NO (2), and [NH2(CH3)2][Mg3(MDIP)(HMDIP)(C3H7NO)]·4H2O (3) (DMF = N,N′-dimethylformamide), have been synthesized by the solvothermal reaction of Co(II), Mn(II), or Mg(II) salts with methylenediisophthalic acid (H4MDIP). All compounds have been characterized by thermogravimetric analysis, IR spectroscopy, elemental and single-crystal X-ray diffraction analyses. Complexes 1–3 are anionic frameworks with [NH2(CH3)2]+ ions occupying the voids, built upon tetra-, tri- and asymmetrical trimetallic cores, respectively. In particular, the asymmetrical trinuclear Mg(II) unit in complex 3 was scarcely observed. Topological analyses show that the three compounds possess binodal (4,8)-connected alb topology with a Schlafli symbol of (410.614.84)(45.6)2. Magnetic investigations indicate that antiferromagnetic couplings are dominant in compounds 1 and 2.

A novel metal–organic framework [Cu3(m-TATB)2Py(CH3OH)2] (1) constructed of a triazine-based trigonal-planar ligand, 3,3′,3″-s-triazine-2,4,6-triyltribenzoate (m-H3TATB), has been synthesized and structurally characterized. Compound 1 features three-dimensional (3D) channels and cavities together, and exhibits high carbon dioxide sorption at normal pressure.

A novel metal–organic framework with unprecedented interweaving of coaxial single-helical and equal double-helical chains of opposite chirality, which features a super-connective helix simultaneously tangling with eight helices, was reported.