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The hydrothermal reaction of silver nitrate and 2,2′-phosphinico-dibenzoic acid (H3L) with different metal to ligand ratios under hydrothermal conditions yielded two unusual complexes with the formulae of [Ag(H2L)]n (1) and [Ag3(L)]n (2). Both complexes were well characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopic and fluorescence studies. Complex 1 crystallizes in a centrosymmetric Pbcn space group and presents a two-dimensional (2D) layer structure through silver(I)-aromatic interaction, whereas complex 2 adopts a noncentrosymmetric Iba2 space group, in which the different coordination modes of the four groups around the phosphorus atom in the L3− ligand occurs. Both complexes display green emissions, assigned as the ligand-to-metal charge-transfer character.

Hydrothermal reaction of Ln(NO3)·6H2O with benzimidazole-5,6-dicarboxylic acid (H3bidc) and KSCN afforded a series of new two- and three-dimensional coordination polymers, namely [Ln2(Hbidc)2(SO4)(H2O)3]n (Ln = La (1), Pr (2), Sm (3), Gd (4)) and [Ln4(Hbidc)4(SO4)2]n·2nH2O (Ln = Eu (5), Tb (6), Dy (7), Er (8)). The sulfates were in situ generated by catalytic oxidation of KSCN. These complexes were characterized by single crystal X-ray diffraction, IR spectroscopy, thermal analysis, fluorescent spectra and magnetic measurements. Complexes 1–4 are isomorphous and comprise a 2D network based upon planar tetranuclear lanthanide secondary building units. The 2D layers extend to a 3D framework by π–π stacking between imidazole rings and hydrogen bonding interactions. The complexes 5–8 are also isomorphous and have similar 3D frameworks fabricated through Hbidc2− and SO42− bridging dinuclear lanthanide secondary building units, and the guest water molecules are trapped in the lattice. The luminescent properties of complexes 5 and 6 exhibit characteristic europium and terbium luminescence, while 4 involves ligand-to-metal charge transfer. The magnetic properties of four complexes were also investigated.

A series of new 3-D boratopolyoxovanadates {K2V12B18O54(OH)6(H2O)[K8(H2O)16]}·3H2O (1), {K10V12B18O54(OH)6(H2O)}·14H2O (2), {V12B18O54(OH)6(H2O)[K6(H2O)12]}·2(H2dien)·3H2O (3, dien = diethylenetriamine), {V6B20O44(OH)8(H2O)[K8(H2O)6]} (4), and {V6B20O44(OH)8(H2O)[K(H2O)]2}·2(H3dien)·6H2O (5) have been hydrothermally synthesized and structurally characterized. These compounds contain five types of [KxOy]n building units, namely, a dimeric [K2O16] unit for 5, a 1-D [K3O12]n chain for 3, a 3-D [K5O10]n sub-network for 1, a 3-D [K5O12]n sub-network for 2, and a 3-D [K4O7]n sub-network for 4. The 3-D frameworks of both 1 and 2 are built up from a different 3-D inorganic [KxOy]n sub-network and entrapped [V12B18O54(OH)6(H2O)]10− (denoted as [V12B18]) clusters, respectively. 3 contains [V12B18] clusters and 1-D [K3O12]n chains, which are interconnected to form a 3-D {V12B18O54(OH)6(H2O)[K6(H2O)12]}n architecture with 1-D tunnels filled with protonated H2dien2+ ions. The 3-D architecture of 4 is constructed by another rare 3-D inorganic [K4O7]n sub-network and entrapped [V6B20O44(OH)8(H2O)] (denoted as V6B20) clusters. Compounds 1, 2 and 4 represent rare examples of extended POVs with the 3-D inorganic [KxOy]n sub-networks. 5 contains [V6B20] clusters and dimeric [K2O16] units, which are interconnected to give a 3-D {B20V6O44(OH)8(H2O)[K(H2O)]2}n architecture with 1-D tunnels filled with protonated H3dien3+ ions. Although a few boratopolyoxovanadates contain the [V6B20] cluster, they display either a discrete [V6B20] cluster or a low-dimensional extended structure. Therefore, both 4 and 5 are rare examples of 3-D boratopolyoxovanadate architectures based on the [V6B20] clusters. The magnetic susceptibilities of both 4 and 5 show the antiferromagnetic interaction between VIV cations. Their spectroscopic properties were also investigated.

Three new 3-D polyoxovanadoborates {[Cu(dien)(H2O)]3V12B18O54(OH)6(H2O)}·4H3O·5.5H2O (1, dien = diethylenetriamine), {[Cd(H2O)2]3V12B18O54(OH)6(H2O)}·4H3O·9.5H2O (2) and {[Na(H2O)3]4Na2V12B18O56(OH)4(H2O)}(H3dien)2 (3) have been hydrothermally synthesized and structurally characterized. Compounds 1–3 contain vanadoborate cluster [V12B18O60] constructed by two hexameric oxovanadate units [V6O9] and one puckered [B18O42] ring via sharing O atoms. The vanadoborate cage [V12B18O60] can present different degrees of protonation, namely [V12B18O60H6]10− for 1 and 2, [V12B18O60H4]12− for 3. The clusters [V12B18O60H6]10− in 1 are connected by complex cations [Cu(dien)(H2O)]2+ into a new 3-D framework via all terminal O atoms of square-pyramidal [VO5] groups, while the clusters [V12B18O60H6]10−/[V12B18O60H4]12− in 2 and 3 are linked with [Cd(H2O)2]2+ groups/the combination of [Na(H2O)3]+ and Na+ ions to give another two types of new 3-D frameworks via O atoms of [BOx] (x = 3, 4) polyhedra, respectively. Magnetic measurements illustrate that compounds 1 and 2 have antiferromagnetic exchange interactions between metal centers. The theoretical band structure of 2 has been also studied.

The reactions of copper(II) ions with azido ligands in the presence of different chelating amine ligands gave three one dimensional copper-azido molecular tapes, [Cu2(N-Pren)(N3)4]n (1), [Cu2(N-Buen)(N3)4]n (2) and [Cu3(tren)(N3)6]n (3) [N-Pren = N-propylethylenediamine; N-Buen = N-butylethylenediamine; tren = tris(2-aminoethyl)amine]. Complexes 1 and 2 are composed of 1D coordination chains based on the step-like tetranuclear copper(II) clusters which feature three types of azido bridging modes (μ-1,1, μ-1,3 and μ-1,1,1). Complex 3 is a novel 1D molecular tape featuring zigzag hexanuclear copper-azido subunits with only end-on azido bridges. Magnetic studies show ferromagnetic coupling in 1 and 2, and antiferromagnetic coupling in 3. The magnetic data for 1 and 2 were fitted with a tetranuclear copper theoretical model.