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Hydrothermal reaction of flexible 4,4′-oxybis(benzoic acid) (H2oba), semi-rigid 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and Cu(OH)2 led to an interesting 2D → 3D polythreaded architecture of MOF [Cu2(bpt)2(oba)2(H2O)]n·4nH2O (1). Accomplished with the rising synthesis temperature, two chiral MOFs [Cu4(bpt)4(oba)4]n (L-2 and D-2), have been obtained from the congenetic nonchiral precursors upon spontaneous resolution, which represent a rarely example of temperature-induced threefold interpenetrating enantiomerically arm-shaped MOFs constructed from achiral symmetrical ligands.

Two new symmetrical tripod thioether tricarboxylic acid ligands, 1,3,5-tris(4-carboxyphenylsulfanylmethyl) benzene and 1,3,5-tris(4-carboxyphenylsulfanylmethyl)-2,4,6-trimethylbenzene (H3L and CH3-H3L) have been designed and synthesized. The reaction of two ligands with Cu2+ ions afforded two Cu-based cluster coordination polymers (CPs), [Cu3L]n (1) and {[Cu(CH3-HL)DMF]·DMF}n (2). It was interesting to note that the substituent groups on central phenyl rings in ligands caused the bend tripodal and planar geometries as well as different coordinated modes for H3L and CH3-H3L, respectively, leading to different structures of CPs 1 and 2. 1 with monovalent Cu+ ions shows a 3D layer-stacking framework with hexanuclear [Cu6(CO2)6] clusters, while 2 with divalent Cu2+ ions forms a 1D chain with dinuclear [Cu2(CO2)4] paddlewheel clusters. 1 shows strong orange fluorescence and exhibits fluorescence sensing for Cr2O42− and Fe3+ ions with good selectivity and sensitivity.

Two isostructural Ln-MOFs, [H 2 N(CH 3 ) 2 ][Ln(cppa) 2 (H 2 O) 2 ] (Ln = Tb/Eu CTGU-1Tb /- 1Eu , H 2 cppa = 5-(4-carboxyphenyl)picolinic acid), were selected to investigate the effects of the different metal centre on the sensing properties. CTGU-1Eu can detect small organic molecule acetone and nitroaromatic explosives in water, whereas CTGU-1Tb can only detect explosive nitrophenol in water.

In search of lanthanide single-molecule magnets, a novel dinuclear dysprosium complex, namely [Dy2(L)2(DBM)2(DMF)2]·3CH3OH (1) (H2L = 2-((2-hydroxy-3-methoxybenzylidene)amino)acetic acid, HDBM = dibenzoylmethane), was synthesized, structurally and magnetically characterized. Single-crystal X-ray structural analysis reveals that the key feature of 1 is neutral dinuclear complex, in which two Dy(III) ions with eight-coordinated environment are bridged by two phenoxido oxygen atoms of two o-vanillin Schiff base ligands. Electrospray ionization mass spectrometry (ESI-MS) results revealed that the intact framework of complex 1 stable in methanol solution. Its magnetic susceptibilities to an alternating current revealed that complex 1 exhibits single-molecule magnet behaviour.

To seek novel dysprosium based single-molecule magnets, a dinuclear dysprosium complex, namely [Dy2(L)2(DBM)2(DMF)2]·2DMF (1) was successfully obtained by employing tridentate Schiff base ligand (where H2L = 2-hydroxy-N′’-(2-hydroxy-3-methoxybenzylidene) benzohydrazide), HDBM = dibenzoylmethane, DMF = dimethylformamide). Single-crystal X-ray structural analysis reveals that the key feature of 1 is neutral dinuclear complex, in which two Dy(III) ions with eight-coordinated environment are bridged by two phenoxido oxygen atoms from two Schiff base ligands. Interestingly, complex 1 could be regarded as the structurally related derivatives to our previous reported complex of [Dy2(L)2(DBM)2(DMF)2] (1a) but adding two guest DMF solvents. More importantly, the energy barrier to magnetic relaxation of 1 is slightly higher, with a value of 33 K, when compared to the corresponding complex 1a of 24 K, which provides a good example towards regulating magnetization dynamics in dinuclear dysprosium (III) single-molecule magnets by guest solvent molecules.

The combination of polystyrene spheres with porous ZIF-8 can induce the formation of a polystyrene @ZIF-8 core-shell structure. The polystyrene microspheres are then removed by an etching process to create a unique hollow ZIF-8. Finally, the adsorption process of the shell on small molecule dyes and drugs was studied.

Two new 3D coordination polymers, [Zn3(L)2(H2O)4]·H2O (1) and [Zn5(μ3-OH)4(L)2(H2O)2] (2) (H3L = 3-(2′,5′-dicarboxylphenyl)benzoic acid), have been synthesized under hydrothermal conditions by adding different amounts of NaOH. Structural analyses show that both of them contain 1D inorganic Zn(II)-chains as rod-shaped secondary building units (SBUs) but they are in different forms. The rod-shaped Zn(II)-chain of 1 is only Zn-carboxylate chain, while the one in 2 is formed by the independent Zn5(COO)6 clusters connected by hydroxyl oxygen. Furthermore, the thermal and luminescent properties of both compounds have been studied.

Based on the N-donor auxiliary ligand effect, two new Ni(II) coordination polymers [Ni2(HL)2(bpe)2] (1) and [Ni(HL)(bipy)(H2O)2] (2) [H3L = 2-(4′-carboxyphenyl)terephthalic acid; bpe = 1,2-bis(4-pyridyl)ethane; bipy = 4,4′-bipyridine] have been successfully synthesized and characterized by single-crystal X-ray diffraction study, elemental analysis, IR spectra, TGA and powder X-ray diffraction (PXRD). This work presents a comparative study on the tuning of structural topologies by using two N-donor ligands with different lengths as auxiliary ligands. The structural determination reveals that complex 1, incorporating bpe ligands, features a three-dimensional (3D) 4-connected 4-fold dia interpenetrating architecture with the point symbol of 66, while 2, containing bipy ligands, exhibits a two-dimensional (2D) sql layer structure with a 4-connected (44·62) topology. Moreover, the magnetic properties for 1 and 2 were also measured and compared on account of their different structures.

The first use of H4nbtc ligand afford a novel 2D Cu(II) metal-cluster-based coordination polymer (MCCP), [Cu4(nbtc)1.5(μ3-OH)2(H2O)4·8H2O (1) (H4nbtc = 6,6′-dinitro-2,2′,4,4′-biphenyl tetracarboxylic acid), in which the boat- and chair-shaped tetranuclear cooper (II) clusters [Cu4(μ3-OH)2]6+ coexist unprecedentedly. Interestingly, the chair-shaped CuII4 cluster-based 1D ladder chain perfectly threaded into the rectangle windows of the 2D grids constructed by boat-shaped CuII4 clusters and H4nbtc. And the magnetic property has also been investigated.

An unusual three-dimensional Co(II)-based pillar-layered coordination polymer [Co 2 (L)(bipy)(OH)(H 2 O)] n ·nCH 3 CN ( 1 , H 3 L = 2-(2′,4′-dicarboxylphenoxy)benzoic acid, bipy = 4,4′-bipyridine), has been successfully yielded via the mixed ligand approach under hydrothermal condition, and characterized carefully by elemental analysis, infrared spectra, and single crystal X-ray diffraction, and magnetic measurement. Single crystal X-ray analysis reveals that the framework of complex 1 is firstly assembled by the 2D undulated layers, and then further supported by bipy spacers into a 3D intricate framework. Topologically, 1 shows a 3D binodal (3,8)-connected tfz - d net with the Schlafli symbol of (4 3 ) 2 (4 6 ·6 18 ·8 4 ), which is less common and rarely found in the reported literatures. Moreover, the magnetic analysis indicates that 1 exhibits the antiferromagnetic coupling interaction between Co(II) ions.

Two different alkaline earth metal coordination polymers (AE-CPs) {[Ca3L2(H2O)6]·2H2O}n (1) and [Sr(H2L)2]n (2) were constructed from using 5-(ethyl oxamate)-isophthalic acid (H2EtL) ligand with alkaline earth metal ions Ca2+ and Sr2+ under solvothermal conditions, respectively. Among them, L and H2L are formed by in-situ hydrolysis of H2EtL, which display multiple kinds of coordinated modes through oxamate and carboxylate groups. 1 and 2 both show three-dimensional coordination frameworks possessing unprecedented (3,4,5)-connected skg1 topology and (3,6)-connected ant topology, respectively. The solid-state fluorescence properties of 1 and 2 were studied, and 1 with bright blue luminescence reveals selective sensing toward Fe3+ ion in water with the low detection limit (LOD) of 1.04 × 10−3 M.

A new one-dimensional (1D) 4d–4f heterometallic coordination polymer [ErAg(Himdc)2(H2O)3] (1) (H3imdc = 4,5-imidazoledicarboxylic acid) is synthesized under hydrothermal condition and characterized by elemental analysis, IR, PXRD and single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic space group P-1, showing a 1D metal–organic pseudo-nanotube with a 4.014 × 12.027 A2 cross-section. Furthermore, it assembles into a 3D supramolecular architecture via hydrogen bonds between pseudo-nanotubes. The complex 1 exhibits solid-state photoluminescence and high thermal stability.

Exceptional 3D Pb(II) MOFs constructed by Pb5(II) cluster motifs have been obtained by hydrothermal reaction of hydrophilic 3-(4-carboxyphenoxy)phthalic acid (H3L) and acetate lead in aqueous solution. Specifically, in this system, an obvious selective reaction of Pb(OAC)2 and H3L has been found. No matter the N-containing heterocyclic auxiliary ligands exist or not, the same products without auxiliary ligand are generated. Moreover, the luminescent property of 1 has also been investigated.

A new 1D Pb(II) coordination polymer, {[Pb(Hbidc)(phen)]·H2O}n (1), has been synthesized by a solvothermal method based on 1H-benzimidazole-5,6-dicarboxylato (H3bidc) and 1,10-phenanthroline (phen). Complex 1 features two types of helical chains, a 1D left- and right-handed double-stranded helical chain and a supramolecular helical chain, which interweave into a new (3,3,6)-connected achiral 3D supramolecular network. Notably, the supramolecular helical chains are induced by the different spatial orientations of the 1D double-stranded helical chains. The structure and properties of 1 have been determined by single crystal X-ray diffraction, powder X-ray diffraction (PXRD), elemental analysis (EA), thermogravimetric (TG) analysis and solid state fluorescence spectra.

The synthesis, structure and magnetic property of a new coordination network {[Co2(bcp)2(bipy)]}n (1) (H2bcp = 1,3-bis(4-carboxy-phenoxy)propane and bipy = 4,4′-pyridine), are reported. Compound 1 shows two identical 2D layers with 22.48.65 topology which are interpenetrated in a parallel fashion, resulting in a twofold interpenetrating motif containing polyrotaxane and polycatenane characters. Magnetic susceptibility indicated the antiferromagnetic exchange interaction. The magnetic behavior of 1 can be explained by the tilts of local distortion axes.

A new coordination compound [Ag(Hcpob)(bpy)] n ( 1 ) was assembled by 4-(3′-carboxylphenoxy)benzoic acid (H 2 cpob), 4,4′-bipyridine (bpy) and AgNO 3 under the hydrothermal synthesis. Especially, H 2 cpob came from the in situ decarboxylation of 4-(2′,3′-dicarboxylphenoxy)benzoic acid (H 3 dpob) in the hydrothermal reaction. Single-crystal X-ray diffraction reveals that 1 crystallizes in a monoclinic P 2 1 /c space group. 1 displays a one-dimensional (1D) fishbone-like double chain structure constructed from Ag(I) ions, bpy ligands and partly deprotonated H 2 dpob ligands, which further form a three-dimensional (3D) supramolecular architecture via π–π stacking and hydrogen-bonding interactions. In addition, the photoluminescence of 1 has been investigated in detail.

The first transition–metal coordination polymer {[Cd2L2(H2O)2]·2H2O}n (1) based on a new 1,2,4-triazole derivatives H2L (H2L = 3-(pyrid-2-yl)-5-(1 H-1,2,4-triazol-3-yl)-1,2,4-triazole) is presented, which not only exhibits an example assembled from 1D [Cd1L] chains to 3D (3,4)-connected network linked through [Cd2(trz)]2 dimeric units, but also shows high thermal stability and strong photoluminescence at room temperature.

A new two-dimensional Cu(I)-framework [Cu3(deppz)(mtta)I] (1) [(Hdeppz = 3,5-diethyl-4-(4-pyridyl)-pyrazole, Hmtta = 5-methyltetrazole] has been solvothermally synthesized and structurally characterized. The framework contains an unprecedented cyclic Cu4(μ-pz)2(μ-mtta)2 cluster (Cu4) with twelve-membered coplanar Cu4N8 metallocycle, which contains coordinatively unsaturated Cu(I) centers and acts as a soft π-acid motif to contact with iodine atoms from Cu2I2 dimer of adjacent layers, generating a 3D supramolecular framework. The framework exhibits high thermostability and bright green-blue solid-state luminescence.

The synthesis, structure and magnetic property of a new coordination network {[Co2(bcp)2(bpt)2]·2H2O}n (1) (H2bcp = 1,3-bis(4-carboxy-phenoxy)propane and bpt = 2,5-bis(4-pyridyl)-1,3,4-thiadiazole), is reported. Complex 1 shows a 3D 48.66.8 topology with unusual self-penetration, in which represents a new example of 6-connected networks. In addition, the magnetic property of 1 has also been investigated.

A new metal-organic framework (MOF), [Zn3(4,4’-ADB)3(BIB)2]n (1) has been synthesized based on mixed bridging ligands BIB and 4,4’-ADB (BIB = 1,4-bis(2-methyl-imidazol-1-yl) butane, 4,4’-ADB = azobenzene-4,4’-dicarboxylica acid). This MOF is a 3D structure with trinuclear zinc(II) clusters as SBU. The trinuclear zinc (II) clusters of line style feature zincs in two tetrahedral and one octahedral coordination environments. The MOF exhibits a 3-fold interpenetrated framework with 36·418·53·6 topology, which reduces the effective void but stabilizes the compound.

A new three-dimensional terbium-carboxylate framework [Tb4L3(H2O)9]·7H2O (1) [(H4L = 4,4′-(hexafluoroisopropylidene)diphthalic acid)] has been hydrothermally synthesized and structurally characterized. The framework contains Tb2 and Tb4 clusters, and exhibits an unprecedented 4-nodal (3,4,5,8)-connected topology. In addition, the thermogravimetric analysis, luminescent and magnetic properties were investigated.

Two new metal-organic frameworks, [M2(CTA)(bipy)1.5(H2O)2]n·3n(H2O) (M = Cd for 1 and Mn for 2, H4CTA = cyclohexane-1,2,4,5-tetracarboxylic acid, bipy = 4,4′-bipyridine) have been successfully synthesized and characterized. Complexes 1 and 2 are isostructural, which display unusual three-dimensional (3D) self-penetrating coordination frameworks with 3-nodal (3,5,5)-connectivity and the Schlafli symbol of (4,6,8)(42,67,8)(43,63,83,9). Moreover, in solid state, complex 1 exhibits blue emission at ambient temperature. Magnetic measurement shows that there exist weak antiferromagnetic interactions in 2.

An unusual 3D pillared-layer CoII coordination polymer, namely [Co(pda)(bpe)]n (1) [H2pda = 1,3-phenylenediacetic acid, bpe = 1,2-bi(4-pyridyl)ethylene], has been successfully prepared under hydrothermal condition. X-ray crystal analysis indicates that the structure of 1 is constructed from 2D undulated [Co(pda)]n layers, which consists of alternating left- and right-handed helical motifs, and then further pillared by bpe ligands into a 3D structural framework. Topologically, complex 1 shows an intriguing binodal (3,5)-connected fsc network with the Schlafli symbol of (4.62)(4.66.83) which is completely different from the reported (4,6)-connected fsc nets; and if the dimeric [Co2] units (SBUs) are considered as the single 6-connected nodes, 1 displays a familiar uninodal pcu net with the Schlafli symbol of (412.63). In addition, magnetic measurement revealed that 1 shows the antiferromagnetic coupling between CoII ions.

Three coordination polymers containing 2-(2-pyridyl)benzimidazole (PyHBIm) ligand, namely {[Zn3(PyBIm)3(PyHBIm)2(tma)(H2O)]•H2O}n (1), [Zn(PyHBIm)(oba)]n (2), [Cd(PyHBIm)(oba)]n (3), (tma = trimesate, oba = 4,4′-oxybis-(benzoate)), have been prepared through hydrothermal reaction. Compound 1 exhibits one-dimensional (1D) helical structure. However, compounds 2 and 3 display 1D meso-helical structure. These 1D structures are further assembled into three-dimensional (3D) networks through aromatic π–π stacking interactions and hydrogen bonding interactions. Moreover they all exhibit strong photoluminescence at room temperature and may be good candidates for potential luminescence materials.

A novel 3D coordination framework [Pb2(hfipbb)2(bpp)]n (1) [H2hfipbb = 4,4′-(hexa-fluoroisopropylidene)bis(benzoic acid), bpp = 1,3-bis(4-pyridyl)propane] based on inorganic rod-shaped infinite Pb–O–Pb chain is presented, which possesses a new (4,5)-connected network topology and shows high thermal stability and strong photoluminescence at room temperature.

A new CdII-coordination polymer, namely, [Cd3(nbtc)2·4H2O]n (1), has been hydrothermally synthesized with in situ generated 5-nitrobenzene-1,2,3-tricarboxylate (nbtc3−) ligand. Single-crystal X-ray diffraction study reveals that compound 1 is constructed from trinuclear CdII clusters and exhibits a previously unknown 2D (3,4,9)-connected (3.42)(32.43.5)(36.411.510.68.8) topology as well as 3D H-bonding pillared architecture. In addition, the photoluminescent property and thermal stability of 1 were also discussed.

The chiral diamondoidlike Cd(II) containing coordination polymer {[Cd(oba)(bib)]·2H2O}n (1) (oba = 4,4′-oxybis(benzoate), bib = 1,4-bis(2-methyl-imidazol-1-yl)butane) is reported; the 3D networks interpenetrate fivefold, nevertheless leave cavities capable of including sizable guest molecules. This compound also exhibits high thermal stability and blue-shift emission, and can be explored for potential blue luminescent materials.

Via hydrothermal synthesis, the self-assembly of d10 metal, 2,4′-dipyridylamine (L) and 1,3-adamantanediacetic acid (H2ADA) generated two unprecedented coordination polymers [Zn(ADA)(L)]n (1) and [Cd(ADA)(L)2]n (2). Complex 1 possesses a novel 1D looped-chain topology structure decorated with arms. Complex 2 shows an extended threaded framework involving 2D coordination layers of square (44) topology with dangling ligands, which gives the novel (2D → 3D) polythreaded array. To the best of our knowledge, complex 2 is the first example with four dangling arms coordinated in the axial sites of dinuclear nodes. In addition, both of the complexes show strong photoluminescence at room temperature, and may be good candidates for potential luminescence materials.

In flexible co-ligand system, the P-handed [Cd(bpb)]n and the M-handed [Cd(pda)]n helical chains interweave mutually into a novel 3D coordination framework with diamondoid skeleton, namely, {[Cd(1,4-pda)(bpb)(H2O)]·H2O}n (1) [bpb = 1,4-bi(4-pyridyl)butane , 1,4-H2pda = 1,4-phenylenediacetic acid ]. Interestingly, 1D hydrophilic tunnel of 1 acts as a template for the formation of the P-handed 1D helical water chains, displaying molecular recognition and chirality transfer. The photoluminescent property and thermal stability of 1 were also discussed.

Two novel 1D compounds {[Ag 3 (Hbptc)(bpa) 2 ]·H 2 O} n ( 1 ) and [Ag 2 (H 2 bptc)(bpp) 2 ] n ( 2 ) (H 4 bptc = 3,3′,4,4′-benzophenonetetracarboxylic acid, bpa = 1,2-bis(4-pyridyl)ethane and bpp = 1,3-bis(4-pyridyl)propane) were synthesized and structurally characterized. The crystal structures of compounds exhibit two kinds of ladder-like chains based on linear or T-shaped coordination environment of Ag(I). Fluorescence spectra of compounds 1 and 2 indicate the unusual intensity of fluorescent emission upon photoexcitation which may be attributed to ligand-to-metal charge transfer and Ag–Ag interactions.

Two new isomeric complexes, namely {[Cu(fum)(tpy)] · 5H2O}n (1) and [Cu2(fum)2(tpy)2] · 4H2O (2), have been synthesized simultaneously from the reaction of Cu(fum) with tpy (where fum = fumarate, tpy = 2,2′:6′,2″-terpyridine) under mild condition. The crystal structures of complexes were determined by X-ray single-crystal diffraction. Complex 1 stabilizes in an unusual 1D water tape notated T4(2)10(2), which is directed by two chiral helical water chains; binuclear complex 2 represents a complicated (6, 3)-connected framework via supramolecular interactions. Additionally, complex 1 exhibits weak ferromagnetic behavior.

A novel coordination polymer based on silver(І) and mixed ligands {[Ag2(bpdc)(bpp)(H2O)] · 2H2O}n (1) (H2bpdc = 2,2′-bipyridyl-4,4′-dicarboxylic acid, bpp = 1,3-bis(4-pyridyl)propane), has been prepared by hydrothermal method. Compound 1 has a 2D polymeric structure extended with subunits tetranuclear silver with Schlafli symbol {3^12;4^9;5^6;6^9}{3^18;4^22;5^5}. Compound 1 represents an Ag-containing polymeric compound possessing room-temperature luminescence.

A well-resolved 2D supramolecular water layer, which self-assembled by (H2O)40 water morphology templating via tartrate dianion, has been observed in the compound [Cu2(tar)(2,2′-bipy)4]tar · 12H2O(1) [tar = tartrate dianion]. Hydrogen bonding interactions between the 2D layers of water and binuclear moieties create a unique, infinite 3D supramolecular edifice.

Rectangle-like tetrameric water clusters associate with sulfate anions and coordinated water molecules into a 2D honeycomb-like layer via hydrogen-bonded interactions. The 2D layer acts as “host” supporting the metal–organic “guest” into a 3D supramolecular architecture.

The new complex {[Cu(dde)(bpe)] · H2O}n (1) (dde = 4,4′-dicarboxydiphenyl ether, bpe = 1,2-bis(4-pyridyl)ethene) has been synthesized and characterized. It exhibits a novel (2D → 3D) three-fold parallel interpenetrating architecture that is obtained for the first time from the self-assembly of grid-containing 2D (4, 4) layer motifs. The fluorescent property of 1 is discussed.

The self-assembly of Cu2+ ions with malate and 1,3-bis(4-pyridyl)propane (bpp) affords a 3D coordination polymer {[Cu(Hmal)(bpp) · 6H2O]}n (1) (malic acid = H3mal). The metal ions were interconnected by α- and β-carboxylate of malate produce infinite [Cu(C4H4O5)]n layers, which were further pillared by bridging ligand bpp molecules to form a 3D interpenetrating network. Of further interest, lattice water molecules form 1D infinite water tapes in 1D open cavities.

A 2D network complex [Ag2(pydco)]n (1) (pydco = pyridine-2,6-dicarboxylic acid N-oxide) was synthesized and structurally characterized. Fluorescence spectrum of complex 1 and the free ligand indicates that the cooperative association of Ag–Ag contacts and the intraligand (π–π∗) interactions lead to the unusual intense fluorescent emission upon photoexcitation.

A new 3D metal–organic framework [Cd2(2,6-pydc)2(bime)(H2O)]n (1) containing 1D Cd − oxygen chains was synthesized by the self-assembly of pyridine-2,6-dicarboxylate (2,6-pydc), 1,6-Bis (imidazol) hexane (bime) and Cd(II) salt, which exhibits a 2-fold interpenetrated 3D entanglement architecture with attractive helical structure. In addition, photoluminescent and thermal properties of complex 1 have been investigated as well.

A new metal-organic framework, namely, {[Co2(oba)2(bib)]·H2O}n (1) (H2oba = 4,4′-oxybis(benzoic acid) and bib = 1,4-bis(2-methyl-imidazol-1-yl)butane), was prepared via self-assembly of the bib with cobalt salt in the presence of V-shaped oba ligand under mild condition. The structure of polymer 1 presents a six-connected self-interpenetrating 44.610.8 topological network with interweaving helical chains. In addition, the most stable conformation of bib has been analyzed by B3LYP calculation.