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Three new lanthanide complexes based on a nitronyl nitroxide radical [Ln(hfac)3(NIT3Ph3Py)]2 (Ln = Dy(1), Tb(2), Gd(3); hfac = hexafluoroacetylacetonate, NIT3Ph3Py = 2-(3′-(3″-pyridyl)-phenyl)-4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide) have been successfully synthesized, characterized structurally and magnetically. Single crystal X-ray diffraction analysis reveals that complexes 1–3 are isomorphous in which NIT3Ph3Py acts as a bridging ligand linking two Ln(III) ions through the nitrogen atom of pyridine ring and the oxygen atom of N O group to form a four-spin system. The magnetic studies reveal that the ferromagnetic interactions between the Ln(III) ions and nitronyl nitroxide radicals in the complexes. Moreover, alternating current (ac) magnetic susceptibilities show that Dy(III) complex exhibits frequency-dependent signals at low temperature.

• Two novel ternary Zn II -triazole-polycarboxylate framework has been synthesized and characterized.

A novel (4, 12)-connected metal-organic framework, {(NH4)2·[Co11(μ4-OH)6(CN)6(trz)12]}n, was solvothermally constructed from unusual CoII8 cubes, octahedral CoII1 subunits, and μ3-N1,N2,N4-triazolate (trz) connectors. Strong antiferromagnetic coupling between the neighboring CoII ions results in an absence of long-range magnetic ordering, leading to a strong spin-frustration with f > 62.

A field-induced MnIII-based single-ion magnet with axially elongated Jahn–Teller distortion was well isolated in a layered complex by diamagnetic NaI ions, which exhibits an effective thermal-activated energy barrier of 12.9 cm− 1 under 2.0 kOe dc field resulting from strongly axial anisotropy of the high-spin MnIII ion.

Two methylammonium-templated metal vanadates, namely [CH3NH3]2MV2O7 (M = Mn (1) and Cd (2)), have been solvothermally synthesized and characterized by IR, TGA, UV–Vis, single-crystal X-ray diffraction (XRD) and Powder XRD, etc. These two isostructural compounds feature an open-framework structure constructed by MO6 octahedra and V2O7 dimers. The methylammonium cations are located in the channels of the framework and act as bi-functional charge-compensating and structure-directing agents. Compound 1 exhibits an effective adsorption performance towards Eu3+ by means of ion exchange. Magnetic study reveals the antiferromagnetic exchange between Mn2+ ions in compound 1.

Hydrothermal reaction of zinc oxide, 1,2-benzenedicarboxylic acid (H2pa) and 1,2,4-triazole (Htrz) yielded a (3,12)-connected 2-D coordination network [Zn8(trz)4(OH)4(pa)4]n (1), in which rare tetragonal prism-like ZnII8 clusters and tridentate 1,2-benzenedicarboxylate act as 12- and 3-connected nodes, respectively. Moreover, the luminescent emission spectra and thermostability of 1 have been investigated.

Two novel two-dimensional copper–nitroxide coordination polymers of formula [Cu2(NIT3Py)2(glu)2]n (1) and {[Cu2(NIT3Py)2(adip)2] · CH3OH · 0.5H2O}n (2) (NIT3Py = 2-(3′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, H2glu = glutaric acid and H2adip = adipic acid), have been synthesized and characterized structurally as well as magnetically. The crystal structures of both polymers contain the paddle-wheel binuclear Cu(II) units axially coordinated by NIT3Py ligands which are bridged by the flexible glutarate or adipate anions into the corrugated 2D sheets. Interestingly, complex 1 displays a 2D helical layer structure rarely found in metal–nitroxide systems. The magnetic measurements show the strong antiferromagnetic interactions in the binuclear Cu(II) units and weak antiferromagnetic interactions between copper ions and nitroxides.

A 3D (3,8)-connected tfz-d framework with unusual Cu5II clusters periodically extended by 5-nitroisophthalate (nip2−) ligands, {[Cu5(μ3-OH)2(μ2-H2O)2(H2O)4(nip)4]·5H2O}n (1), was hydrothermally synthesized and structurally characterized. Magnetically, the spin frustration in a vertex-sharing triangular aligned Cu5II cluster leads essentially to an overall S = 1/2 spin ground state of 1.

A 3D pillared-layer porous framework, {[Co2(H2O)(μ3-OH)(ptz)(nip)]·2H2O}n (1) (ptz = 5-(4-pyridyl)tetrazolate, nip = 5-nitroisophthalate), was in situ hydrothermally synthesized and structurally and magnetically characterized. Interestingly, the layered substructure of 1 consists of scarcely observed corner-sharing Co2(μ3-OH) ∆-chain and unprecedented pentadentate ptz ligand. More importantly, due to the mixed triple syn,syn-carboxylate-μ3-OH-μ4-tetrazolyl bridges as well as the triangular CoII arrangement, 1 behaves as a typical antiferromagnetically coupled paramagnet with a slight spin frustration, which exhibits a low-dimensional antiferromagnetic ordering below 10 K (Neel Temperature).

Two coordination polymers with the same mixed ligands but different metal ion, [Cd5(bpp)6(μ1,1-N3)6(μ2-Cl)2Cl2]n (1) and {[Ni2(bpp)4(N3)4]·0.5H2O}n (2) (bpp = 1,3-bis(4-pyridyl)propane), have been hydrothermally synthesized and fully structural characterized. Complex 1 exhibits an eight-connected bcu-type 3D framework with end-on azido-aggregated neutral pentanuclear clusters periodically extended by neutral bpp linkers. Instead, 2 reveals an interpenetrated 2D (4, 4) undulated layer assembled from the octahedral Ni(II) nodes and bridging bpp connectors with monodentate azide anions terminally attached on both sides. Additionally, in contrast to non-fluorescent 2, solid complex 1 displays an intense luminescent emission resulted from the ligand-to-metal charge-transfer upon the cation binding.