Three polynuclear complexes, [NiNa(μ_1,1,1-N₃)(μ-hmb)₂(DMF)]₂, (1), [Ni₄(μ₃-OMe)₄(heb)₄(MeOH)_1.05(H₂O)_2.95], (2) and [Ni^III(OH)₆(hmb)₆Ni^II ₆]·(ClO₄)₃ (3) (Hhmb = 2-hydroxy-3-methoxy-benzaldehyde; Hheb = 2-hydroxy-3-ethoxy-benzaldehyde), were prepared by reaction of the appropriate ligand with nickel(II) perchloride hexahydrate under solvothermal conditions. All compounds were characterized by elemental analysis, IR spectroscopy and X-ray single-crystal diffraction. Compound 1 exhibits a centrosymmetric heterotetranuclear cluster which represents the first nickel complex to possess two connected face-sharing cubes structure {Ni₂Na₂N₂O₄}. Compound 2 has a tetranuclear Ni cluster with a cubane topology in which the Ni(II) and the oxygen atoms from the methanol ligands occupying alternate vertices of the cube. Compound 3 consisits of a mixed-valence [Ni^III(OH)₆(hmb)₆Ni^II ₆]³⁺ subunits and it represents the first nickel {Ni^II ₆Ni^III} complex to possess a planar hexagonal disc-like structure. The results show that the minor ligand modifications or solvent change have a key role in the structural control of the self-assembly process. Magnetic properties of 1–3 in the 300–2 K have been discussed. The {Ni₂Na₂} (1) and {Ni₄} (2) core display dominant ferromagnetic interactions from the nature of the binding modes through μ₃-N₃ ⁻ or μ₃-OCH₃ ⁻, while {Ni^II ₆Ni^III} core (3) displays dominant anti-ferromagnetic interactions from the nature of the binding modes through μ₃-OH⁻.

Here we report an effective approach for preparing hollow carbon nanospheres with Cu–TiO₂ from a Ti precursor encapsulated surface mounted MOF (SURMOF) coating.

Three new polynuclear complexes, [Co₇(bm)₁₂]·(ClO₄)₂·13H₂O (1), [Co₄(bm)₄Cl₄(C₃H₇OH)₄] (2), and [Co₄(bm)₄(μ-HCO₂)₂(μ₂-HCO₂)₂(C₃H₇OH)₂] (3) (Hbm = (1H-Benzimidazol)-methanol), have been synthesized and characterized by elemental analysis, IR, powder X-ray diffraction and X-ray single-crystal diffraction. Compound 1 features a centrosymmetric wheel-like heptanuclear Co(II) cluster. Compound 2 having a I4₁/a space group exhibits a tetranuclear Co(II) cluster with a cubane topology in which the central Co(II) ion and oxygen atoms from bm occupy the alternate vertices of the cube. However, compound 3 has a tetranuclear Co(II) cluster with a C2/c space group different from that of compound 2. These results show that the geometries and sizes of the corresponding anions as well as their coordinating and hydrogen-bonding properties are essential in determining the final structures of the assemblies. Magnetic properties of 1–3 in the 2–300 K have also been discussed. The {Co₇} (1) and {Co₄} (2) cores display dominant ferromagnetic interactions while the {Co₄} (3) core displays dominant anti-ferromagnetic interactions.

Four coordination polymers, formulated as [Zn(L¹)₂]_n (1), [Cd(L¹)₂]_n (2), [Zn(L²)₂]_n (3) and [Cd(L²)₂]_n (4) (HL¹ is (E)-2-(((4H-1,2,4-triazol-4-yl)imino)methyl)-4,6-dibromophenol; HL² is (E)-2-(((4H-1,2,4-triazol-4-yl)imino)methyl)-4,6-dichlorophenol) have been synthesized through vial reactions. The four compounds were structurally characterized by single crystal X-ray diffraction, elemental analysis, PXRD, and fluorescence spectroscopy. For 1–4, a detailed analysis of Hirshfeld surfaces and fingerprint plots facilitates a comparison of intermolecular interactions, which are crucial in building different supramolecular architectures. C–H⋯X (X = Br, Cl) interactions play a crucial role in stabilizing the self-assembly process among adjacent 2-D networks for both complexes. Above all, complexes 1–4 showed highly intense electrochemical luminescence (ECL) in DMF solution and high thermal stability.