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The ternary combination of CuI, lanthanide cations and electron-deficient viologen based organic tectons led to a donor–acceptor (D–A) hybrid heterostructural framework with a narrow energy gap. Thanks to the electron transfer between inorganic donors (cuprous iodide clusters) and organic acceptors (viologen based tectons), this unique hybrid framework exhibits enhanced photocatalytic activities towards the degradation of rhodamine B (RhB) in comparison with those of lanthanide cations and bulk CuI.

The insertion of electron-rich iodoplumbate nanowires and nanolayers into layered electron-deficient metal-viologen frameworks leads to two donor-acceptor hybrid structures, respectively, which exhibit interesting semiconductor behaviors. Due to the bicontinuous donor and acceptor components, both of them exhibit highly efficient photocatalytic degradation activities over organic dyes under visible light irradiation compared to those of other iodoplumbate hybrid materials.

Based on a multi-dentate salicylhydrazide-derived ligand, a Zn-contained metal–organic gel that could stand for months has been prepared. The driving force within the supramolecular assembly was discussed by studying the gelation conditions, optical spectra, dynamic rheology and mass spectra. These studies revealed that both the coordination bonds and hydrogen bonds participate in the supramolecular assembly. In addition, electrostatic force also played as a key role in stabilizing the gel phase. The charge nature of the colloidal particle is negative charged. Consequently, the xerogel shows significant adsorption behavior that favors positively charged dye molecules, such as methyl violet and methylene blue. The title gel exhibits gelation-induced fluorescence enhancement property. When the gel was exposed to ammonia vapor, a gel–solution transition occurred, accompanied by a great weakening of fluorescence. The phase transition and fluorescence switching were found to be reversible for at least seven cycles. The mechanism involved was studied and discussed.

Herein, we report an unprecedented hybrid structure of electron-rich iodoplumbate nanowires precisely inserted into the periodic pores of electron-deficient pyridinium metal-organic frameworks (MOFs). To the best of our knowledge, this is the first example of semiconductive MOFs in situ loaded with inorganic semiconductive nanowires via a simple self-assembly method. Due to the dissimilar semiconductivities between the host and guest components, this hybrid also represents the first bicontinuous donor-acceptor hybrid at the molecular level based on host-guest interactions.

Metal-ion-directed assembly of naphthalene diimide tectons cooperatively enhanced by anion-π interactions of giant anions, PMo12O40(3-), leads to a novel organic-inorganic hybrid with ultrafast-responsive photochromic properties, which is attributed to the polyoxometalate-sensitized photo-induced radical generation of naphthalene diimide units.

Shape-anisotropic nanomaterials with uniform lengths and widths have attracted much interest but few of them are involved in self-assembled manganese complexes. The combination of two redox-active acylthiosemicarbazide ligands with Mn3+ cations leads to two discrete polynuclear Mn nanorods, pentanuclear [Mn5(L3)6][Mn0.7(DMF)1.4(H2O)2.8] (1a) and trinuclear Mn3(L4)3·2DMF (2), whose L3 and L4 represent N-(5-(2-hydroxyphenyl)-1,3,4-oxadiazol-2-yl)benzamide and N-(5-(2-hydroxyphenyl)-1,3,4-oxadiazol-2-yl)-propionamide, respectively, which are in situ synthesized from their acylthiosemicarbazide derivatives in the presence of Mn3+ cations, while the latter are reduced into divalent ones in rod-like moieties. For each pentanuclear anion in 1a, the charge is balanced by a solvated trivalent manganese cation, which can be replaced by two tetramethylammonium cations to yield pure valence compound 1b. Moreover, the magnetic studies reveal all of them possess antiferromagnetic properties.

A new kind of trinuclear copper(II) motif [Cu3L] was prepared in situ by adopting a multidentate ligand, N′2,N′2′-bis(2-hydroxybenzoyl)biphenyl-2,2′-dicarbohydrazide (H6L), in the presence of a series N-containing agents. Featuring five different assembly styles, [Cu3L(DMF)2.5(hmta)]·3H2O (1), [Cu3L(DMA)(H2O)(Hmor)] (2), [Cu3L(py)2]·DMF (3), [Cu3L(DMF)(H2O)]·2DMF (4), and [Cu3L(DMA)(H2O)]·0.5DMA (5) (hmta = hexamethylenetetramine, Hmor = morphiline, py = pyridine) were obtained. In these assemblies, the [Cu3L] units are connected with each other into one-dimensional chains via bridging of N-containing agents or via sharing an oxygen atom of L6− to fuse together. Furthermore, the connecting styles are found to be governed by the character of the N-containing agents used, which is discussed in detail. Thermal gravimetric analysis and magnetic measurement of some complexes were performed.

A 2-D metal–organic hybrid framework, [(Nd2DMF12IN2)(Pb8I20)]n (HIN = isonicotinic acid) was structurally determined, which was constructed from a lanthanide metal complex and 1-D lead–iodine polymersvia a HIN ligand with mixed coordination sites.

Hydrothermal reactions of divalent transition metal salts with two different-sized tetrazole-yl acylamide ligands, N-(1H-tetrazol-5-yl)acetamide (H-NTAA) and N-(1H-tetrazol-5-yl)propionamide (H-NTPA), led to six crystalline coordination polymers, named Cd(NTAA)2 (1), Zn(NTAA)2·∼H2O (2), Cu(NTAA)2 (3), Mn(NTAA)2 (4), Cd(NTPA)2 (5), Mn(NTPA)2 (6), respectively. The X-ray diffraction analysis revealed that compound 2 is a 1D zigzag chain, compounds 3 and 4 exhibit an interesting 2D 44-sql network, while compounds 1, 5 and 6 possess a 3D non-interpenetrated diamondoid framework. Wherein, compounds 1, 4, 5 and 6 crystallized in an acentric space group with significant second harmonic generation (SHG) efficiencies. The effect of metal ions and that of small aliphatic acyl side-groups in semirigid tetrazole-yl acylamide ligands on the structural topologies and symmetries of generated coordination polymers are discussed.

Using a hydrothermal synthesis method, the combination of four tetrazolate-yl acylamide tectons bearing substituents of different sizes, 4-nitro-N-(1H-tetrazol-5-yl)benzamide (H-NTBAN), 4-fluoro-N-(1H-tetrazol-5-yl)benzamide (H-NTBAF), N-(1H-tetrazol-5-yl)isonicotinamide (H-NTINA) and N-(1H-tetrazol-5-yl)thiophene-2-carboxamide (H-NTTCA), with cadmium dichloride led to four crystalline coordination networks, named Cd3(NTBAN)6 (1), Cd(NTBAF)2 (2), Cd(NTINA)2 (3) and Cd(NTTCA)2 (4), respectively. The X-ray diffraction analysis revealed that compounds 2, 3 and 4 possess a 3D non-interpenetrated diamondoid framework, while compound 1 is of a 0D trinuclear structure. Wherein, compounds 2, 3 and 4 crystallized in chiral space groups with significant second harmonic generation (SHG) efficiencies. The effects of substituents in the semirigid tetrazole-yl acylamide tectons on the structural topologies as well as on the nonlinear optical properties of the generated coordination networks are discussed.

A double-wall-hourglass-shaped metallocavitand bearing an electron-deficient cavity was self-assembled, which exhibited an unusual selectivity to substituted benzene derivatives of different electron density during co-crystallizations.

Two Co(II) and Mn(II) coordination polymers, which have been synthesized under hydrothermal conditions, are isomorphous with magnetic Δ-chains containing trinuclear triangular [M(3)(μ(3)-OH)] clusters. The Δ-chains are bridged by isonicotinic spacers to generate a two-dimensional scalariform layer structure. Magnetic investigations indicate that Co(II) compound exhibits not only spin canting but also metamagnetic behaviors, while only spin-canted antiferromagnetic behaviors was observed in Mn(II) compound.

In this paper, four silver(I) compounds, namely, {[Ag(4)(bipy)(4)(chda)]·2NO(3)·10H(2)O}(n) (1), {[Ag(2)(bipy)(2)(chda)]·14H(2)O}(n) (2), {[Ag(2)(bipy)(2)(chda)]·3EG·2H(2)O}(n) (3) and {[Ag(2)(bipy)(2)(chda)]·H(2)chda}(n) (4) (where bipy = 4,4'-bipyridine, H(2)chda = trans-cyclohexane-dicarboxylate and EG = ethylene glycol), have been synthesized and characterized by single-crystal X-ray diffraction analyses. In all of these compounds, the Ag(I) centers are linked by bipy ligands to form 1D Ag(I)-bipy chain structures. The chda(2-) anions of compound 1 adopt a μ(4)-coordination mode to connect the Ag(I)-bipy chains, forming a H-beam-like chain. In 2, the chda(2-) anions adopt a μ(2)-coordination mode to connect the Ag(I)-bipy chains resulting in two distinct 2D brick wall-like layers. These layers are further stacked in an ···ABAB··· fashion through interlayer π···π stacking interactions giving rise to a 3D framework consisting of quasi-rectangular channels, in which an unusual double T5(2) water tape is trapped. For 3 and 4, the chda(2-) anions show a similar μ(4)-coordination mode to that of 1 and connect the Ag(I)-bipy chains to form 2D grid layers with identical compositions and connective topologies. The experimental studies show that the final structures are greatly influenced by the molar ratio of the components and the solvents, which can be rationally interpreted by the existence of various supramolecular interactions between the host and guest molecules within these compounds through a systematic structural comparison. Additionally, the thermal stability and luminescent properties of these compounds were also studied.

The new ternary metal rich compound Hf27Si6P10 has been synthesized by reduction of HfP with Hf and Si; Hf27Si6P10 crystallizes in a new structure type, a characteristic and unexpected feature of which is the presence of P2 groups; the structural results are interpreted with the aid of high-level band structure calculations.

The introduction of series of organic conjugated ligands into the Pb/I system leads to the formation of three lead(II)/iodine polymers [Pb2I4(dpdo)]n (1) (dpdo = 4,4′-dipyrdiyl-N,N′-dioxide), [PbI2(bipyO2)]n (2) (bipyO2 = 2,2′-dipyrdiyl- N,N′-dioxide) and {[PbI(Dhydql)]∙DMF}n (3) (Dhydql = deprotonated 8-hydroxyquinoline). In 1 and 2, both the organic and inorganic ligands are neutral. But the organic moiety in 3 is a conjugated negative ion and the inorganic component presents a 2-D layer arrangement. The organic ligands in this work serve as bridges to link the inorganic chain or layer to heighten the structural dimension. As expected, based on the bridge nature of an organic ligand, 1 features a 2-D arrangement of a staircase-like lattice sheet [Pb2I4(dpdo)]n, 2 exhibits a 1-D chain [PbI2(bipyO2)]n consisting of unprecedented twisted boat from seven-membered rings, and 3 presents a host–guest structure with DMF as guest molecules which are embedded in between adjoining inorganic–organic components. Furthermore, the compounds were further characterized with fluorescence, UV-vis spectra and third-order non-liner optical (NLO) properties.