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In this work, we systematically report four indium–organic framework (InOF) crystals, which comprise the In(CO2)4 monomer for [InCu(inc)4](NO3) (InOF-5) and [Me2NH2]2[In2(Cu4I4)(pdc)4] (InOF-6), the In(OH)(CO2)2 chain for [In2(Cu4I4)(OH)2(nia)4] (InOF-7), and In3O(CO2)6 clusters for [(In3O)2(Cu4I4)3(nia)12(H2O)6](NO3)2 (InOF-8). With the help of the ligand-oriented bifunctional method, a series of novel heterometallic indium–organic frameworks can be easily achieved through the way the pyridyl N-affinitive sites connect to Cu-based units and the COO–-affinitive sites to In(III) centers. This new strategy will open the door to the construction of multifunctional and heterometallic InOF materials.

A series of metal–organic frameworks (MOFs) were systematically synthesized through a solvent-ratio-controlled assembly: {[Et2NH2]2[Zn5(L)2(H2O)4]·2C2H5OH·2H2O}n (1), {[Et2NH2]4[Zn7(HL)2(H2L)2]·4C2H5OH·6H2O}n (2), {[Et2NH2]4[Zn6(L)2(H2L)(H2O)2]·2C2H5OH·2H2O}n (3), {[Et2NH2]4[Zn4(L)2(H2O)2]·4H2O}n (4), and {[Et2NH2]2[Zn2(L)]·C2H5OH}n (5) (H6L = [1,1′;4′,1″]terphenyl-3,5,2′,5′,3″,5″-hexacarboxylic acid, DEF = N,N-diethylformamide). Along with the altering of ratios of the ternary mixed-solvent DEF/H2O/C2H5OH used in the synthetic processes, the coordination modes of the ligand change, which further leads to the different structures of resultant complexes. Owing to diverse metal centers and clusters and distinct ligand coordination modes, these five complexes exhibit totally different and novel topologies: complex 1 displays a (5,8)-connected 3D net, in which the 8-connected nodes are based on trinuclear metal clusters; complexes 2–4 all exhibit 3D 4-nodal nets based on two kinds of metal centers and two kin...

Two novel high-nuclearity manganese clusters, [Mn14(BSC4A)3(tBuPO3)6(μ4-OH)3Cl(H2O)(CH3OH)]·1.5CH3OH (1) and [Mn16(BSC4A)3(PhPO3)7(HPO4)(μ4-OH)3Cl(H2O)(CH3OH)4]·4.5CH3OH (2) (H4BSC4A = p-tert-butylsulfonylcalix[4]arene; tBuPO3H2 = tert-butylphosphonic acid; PhPO3H2 = phenylphosphonic acid) have been solvothermally obtained and structurally characterized. Crystal structural analyses reveal that the phosphonate ligands have a large influence on the structures of the polynuclear manganese clusters: complex 1 possesses a drum-like MnII14 core, which is constructed from three Mn4–BSC4A molecular building blocks (MBBs) and six tBuPO32− ligands and capped by two MnII ions; while complex 2 has a diamond-like MnII16 core, which also consists of three Mn4–BSC4A MBBs, but connected by seven PhPO32− linkers and a tetrahedral Mn4 cluster housing a phosphate anion generated in situ. To the best of our knowledge, complex 2 gives the first calixarene-based cluster linked by both organic phosphonate and inorganic phosphate ligands, and also presents the highest nuclearity manganese complex with the H4BSC4A ligand to date. Magnetic measurements suggest the presence of antiferromagnetic interactions between the adjacent MnII spin carriers for both complexes.

Two 3D MOFs (1 and 2) have been solvothermally synthesized by introducing a π-electron conjugated fluorescent aromatic polycarboxylate ligand under the modulation of reaction temperature. Intriguingly, complex 2 shows an unusual fluorescence thermochromism. Upon decreasing the temperature, the emission bands exhibit different variation behaviors which result in dramatic changes of the emission color. The fluorescence of 1 and 2 dispersed in DMF (N,N-dimethylformamide) can be selectively and sensitively quenched by using nitro aromatic compounds (NACs) with a fast response time of just 10 s, indicating that 1 and 2 are potential real-time response candidates for detecting NACs. More interestingly, when DNP (2,4-dinitrophenol) and PNA (p-nitroaniline) are introduced, distinctive fluorescence signals, which can discriminate them from other NACs, are observed, making 1 and 2 the rare materials that can distinguish different nitro aromatic molecules.

An unusual bifunctional Tb-MOF (TbL) was synthesized by solvothermal method. Luminescent measurements show that the TbL compound exhibits high sensitivity for Ba2+ ions in DMF solution. Moreover, TbL presents significant selective capture of CO2 from the mixtures of CO2–N2 and CO2–CH4, based on the studies of gas sorption capability. To the best of our knowledge, it is the first reported Tb-MOF with such highly sensitive luminescence response for Ba2+ ions and excellent selectivities for CO2–N2 and CO2–CH4.

Two isostructural porphyrin Zr and Hf metal–organic frameworks (FJI-H6 and FJI-H7) are rationally synthesized, and are constructed from 2.5 nm cubic cages., Two isostructural porphyrin Zr and Hf metal–organic frameworks (FJI-H6 and FJI-H7) are rationally synthesized, and are constructed from 2.5 nm cubic cages. Notably, they both possess high water and chemical stability and can undergo single-crystal to single-crystal transformations to embed Cu2+ ions into the open porphyrin rings. FJI-H6 has a high BET surface area of 5033 m2 g–1. Additionally, they exhibit promising catalytic abilities to convert CO2 and epoxides into cyclic carbonates at ambient conditions.

Reactions of the terphenyl-hexacarboxylate ligand [1,1′;4′,1′′]terphenyl-3,5,2′,5′,3′′,5′′-hexacarboxylic acid (H6L) with Zn(NO)3 in the mixed solvents under low-temperature solvothermal conditions afforded five new coordination networks, namely, {[Me2NH2]2[Zn5(L)2(H2O)4]·16H2O}n (1), {[Me2NH2][Zn(H3L)(H2O)]·C2H5OH·5H2O}n (2), {[Me2NH2]2[Zn2(L)(H2O)2]·2DMF·2H2O}n (3), {[Zn4(L)(COO)2(DMF)2(H2O)2]·2C2H5OH·2DMF·2H2O}n (4), and {[Zn4(L)(DMF)4(C2H5OH)(H2O)](OH)2·DMF·2H2O}n (5) (DMF = N,N-dimethylformamide). Compounds 1 and 3–5 possess 3D frameworks, while compound 2 exhibits a 2D grid layer network. Photoluminescence properties of these five compounds have been investigated in solid state at room temperature and low temperature. These five compounds exhibit two kinds of emission modes at room temperature, and compounds 3–5 turn out to have interesting responses to temperature. The sensing properties of compound 1 also have been explored, which show high selectivity and sensitivity to trace amounts of nitrobenzene.

Two attractive Cu(I) coordination polymers with unique structures, namely, {[Cu8(bptp)4]·6H2O} (1) and {[Cu5(bptp)2(CN)]·2H2O} (2), have been successfully synthesized based on a V-shaped multidentate N-containing ligand 2,6-bis[3-(pyrid-4-yl)-1,2,4-triazolyl]pyridine (H2bptp). The structural analysis reveals that complex 1 displays a Cu8 cluster-based infinite 1D ladder chain, in which each H2bptp ligand links four or five Cu(I) ions through nitrogen atoms of pyridine/triazole groups. Complex 2 features an unusual (3,4,5)-connected 3D topological network with the Schlafli symbol (42·54·63·7)(42·63·7)(5·6·8)(5·62·7·82), which has not been reported before. The structural and dimensional diversity of the two complexes indicates that H2bptp exhibits strong coordination ability and diverse coordination modes. It is worth mentioning that the Cu⋯Cu distances in 1 and 2 are shorter than the sum of the van der Waals radii of copper(I) (2.80 A), implying the metal–metal bonding interactions. What is more, the solid-state luminescence bands of 1 and 2 have also been investigated between 298 and 10 K. Interestingly, the low-energy emission bands of 1 and 2 exhibit yellow/orange-red luminescence, and their intensities increase gradually upon cooling.

The conflict between strength and ductility has been a longstanding dilemma for metallic alloys. Herein, we present a facile strategy to overcome the strength-ductility trade-off of face-center-cubic high-entropy alloys (HEAs) via the in-situ formation of heterogeneous grain structure, using the high local temperature gradients generated during spark plasma sintering coupled with the ‘sluggish diffusion’ of HEAs. The fabricated CoCrFeMnNi HEA has a heterogeneous structure over a large range of grain size from 140 nm to 5 μm, which enables a gigapascal yield strength and a uniform elongation of 9.5%. The mechanism responsible for the associated mechanical properties was analyzed.

Five novel Zn(II)/Cd(II) coordination polymers (CPs) based on the V-shaped ligand 1H-3,5-bis(pyrazinyl)-1,2,4-triazole (Hbpt) and different polycarboxylates, {[Cd(bpt)(H2O)]·ClO4·H2O} (1), {[Cd4(bpt)2(suc)2.5(OH)]·3H2O} (2), {[Cd4(bpt)3(1,3-bdc)2.5]·4H2O} (3), {[Cd9(bpt)6(1,4-bdc)6(H2O)2]·4H2O} (4) and {[Zn2(bpt)(H3bhc)(H2O)6]·H2O} (5) (H2suc = succinic acid, 1,3-H2bdc = isophthalic acid, 1,4-H2bdc = terephthalic acid, H6bhc = benzene-1,2,3,4,5,6-hexacarboxylic acid), have been successfully synthesized. Their structures have been characterized using single-crystal X-ray crystallography, powder X-ray diffraction (PXRD) analyses, elemental analyses, IR spectroscopy, and thermogravimetric analyses (TGA). Complex 1 bears a two-dimensional (2D) layered (3,3) network, which is further extended into the resulting three-dimensional (3D) supramolecular architecture via π⋯π stacking interactions between the terminal pyrazine groups of bpt− ligands. In 2, Cd(II) ions and bpt− ligands construct a 2D Cd-bpt layer and two 1D zigzag chains, which are further connected by suc2− ligands to form a 2D + 1D → 3D (4,5)-connected framework. Complex 3 contains two kinds of grids, and their alternating arrangement gives a final complicated 3,4,5-connected network with a stoichiometry of (3-c)6(4-c)9(5-c)2. In 4, the bpt− ligands act as tetradentate ones to connect neighbouring Cd(II) ions into an infinite 1D Cd-bpt chain. The completely deprotonated 1,4-bdc2− ligands further link the adjacent Cd-bpt chains to generate a novel 3,4,6-connected 3D topological network with (3-c)2(4-c)14(6-c). Complex 5 displays an infinite 1D coordination chain. There are strong π⋯π stacking interactions between adjacent chains in 5 with a centroid–centroid distance of 3.860 A and 3.862 A, resulting in a 3D supramolecular structure. The results show that Hbpt can act as a versatile building block for the construction of various coordination polymers. Moreover, the fluorescence properties of 1–5 in the solid state have also been investigated.

Two novel thiacalix[4]arene-based high-nuclearity cobalt clusters, [Na2Co24(BTC4A)6(PO4)6(HCOO)6(DMC)2(DMF)2(dma)4]·5DMF·9CH3OH (denoted as Na2@Co24, 1) and [KCo24(BTC4A)6(PO4)6(Cl)2(HCOO)4(DMF)8][KCo24(BTC4A)6(PO4)6(Cl)2(HCOO)6(DMF)4(CH3OH)2]·8DMF·23CH3OH (denoted as K@Co24, 2) (H4BTC4A = p-tert-butylthiacalix[4]arene, DMC = N,N′-dimethylcarbamic acid anion, dma = dimethylamine), have been solvothermally prepared and structurally characterized. Compounds 1 and 2 are each capped by six Co4-BTC4A molecular building blocks (MBBs) and six phosphate linkers and other different auxiliary anions, possessing an eicositetranuclear Co24 core templated by alkali-metal cations. In essence, compound 1 is templated by two Na+ cations with an attractive interaction in the center of the core, while 2 is templated by one K+ with a larger radius. Such differences “convert” an oval-shaped Co24 disklike core in 1 to a circular core in 2. Interestingly, 2 contains both anionic and cationic KCo24 cores, representing the large...

A novel coordination polymer, formulated as Zn6(TIB)4(BPTC)3(DMA)4(H2O)10 [TIB=1,3,5-tris(1-imidazolyl)-benzene, H4BPTC=3,3′,5,5′-biphenyltetracarboxylate], has been synthesized and structurally characterized. Further investigations reveal that it presents a new topology (topological symbol {62.84}{63}4{65.8}6{66}2) based on self-penetration, and shows interesting fluorescent properties.

Five d10 transition-metal clusters, {[Zn15(2,6-Hbptp)(2,6-bptp)7(μ2-O)4(μ2-OH)4(HCOO)2(NO3)(H2O)2]·20H2O} (1), {[Zn8(2,6-Hbptp)(2,6-bptp)5(μ3-O)2]·(ClO4)·7H2O} (2), {[Cd8(2,6-Hbptp)2(2,6-bptp)4(μ3-O)2]·(NO3)2·10H2O} (3), {[Ag7(2,6-Hbptp)(2,6-bptp)3]·4H2O·CH3OH}n (4), and {[Ag6(2,6-Hbptp)2(2,6-bptp)2][Ag6(2,6-Hbptp)2(2,6-bptp)2]2·30H2O·4CH3OH} (5), based on bent ligand 2,6-bis[3-(pyrazin-2-yl)-1,2,4-triazolyl]pyridine (2,6-H2bptp) have been synthesized. Compound 1 exhibits a novel fanlike Zn15 cluster, which is the highest-nuclearity Zn cluster with 2,6-H2bptp reported thus far. In 2 or 3 (M = Zn/Cd), each ligand coordinates to three M2+ ions, to form an M8L6 cluster. The structure of compound 4 is a Ag6 cluster-based 1D chain, where each hexanuclear [Ag6(2,6-Hbptp)(2,6-bptp)3]− cluster links its equivalent ones via sharing the Ag atom. Compound 5 contains two kinds of Ag6 clusters, and the alternating arrangement of them gives the final structure. It is worth mentioning that the Ag–Ag bond distances in 4 ...

A family of high-nuclearity M4n (M = Ni or Co, n = 2–6) coordination nanocages constructed by M4–calix[4]arene molecular building blocks (MBBs) with inorganic phosphate or organic phosphonate ligands have been isolated by solvothermal syntheses and characterized by single-crystal X-ray diffraction. This family can be divided into five structural types with an increase in the number of M4–calix[4]arene MBBs, including Ni8 (1 and 2, n = 2), M12 (M = Ni (3) and Co (4), n = 3), M16 (M = Ni (5) and Co (6), n = 4), Co20 (7, n = 5), and Co24 (8, n = 6) coordination nanocages. Structural analyses reveal that the metallic cores of 1 and 2 are arranged in chair conformation, while compounds 3–6 with closed-shell structures, where their ports are sealed by sodium ions, present the first examples of 2p-3d heterometallic metal–calixarene nanocages to our knowledge. The novel helmet-like Co20 (7) is the only one in this family with an open-shell structure, which can be thought of as a truncated octahedral Co24 (8) nano...

A novel luminescent Ag(I) coordination polymer, [Ag3(cpterpy)2]n·nNO3 (1) (Hcpterpy = 4-(4-carboxyphenyl)-2,2:4′,4-terpyridine), is built-up from Ag(I) ions and terpyridyl-carboxylate ligands with unusual three different coordination modes. The dinuclear [Ag2O2] units with cpterpy- ligands in 1 are linked to form 2D wave-like layers and further connected by [Ag4O6] units into a 3D network, which features 3-fold interpenetrating (3,8)-connected nets with a (41264812)(462)(462) topology. Complex 1 exhibits interesting solid-state photoluminescence and high thermal stability.

Six lanthanide coordination polymers of the formula [Ln(L1)0.5(H2O)2]·2H2O [where Ln3+: Eu3+ (1), Tb3+ (2), and Gd3+(3)] and [Me2NH2][Ln(H2L2)(H2O)4]·0.5DMF·xH2O [where Ln3+: Eu3+ (4), Tb3+ (5), and Gd3+(6)], based on p-terphenyl-2,2″,2‴,5,5″,5‴-hexacarboxylate acid (H6L1), and p-terphenyl-3,2″,3″,5,5″,5‴,-hexacarboxylate acid (H6L2), have been solvothermally synthesized and structurally characterized. Complexes 1–3 are 3D frameworks exhibiting 6-connected pcu alpha-Po primitive cubic network with topology (412.63), while complexes 4–6 show two-dimensional (2D) architectures showing simplified 3,4-connected binodal net and (4.62)(42.62.82) topology. Detailed photophysical behaviors have been explored on Eu3+, Tb3+, and Gd3+ complexes. The calculated triplet state energies of H6L1 and H6L2 lie above the emissive levels of Eu3+ or Tb3+ in an ideal range for sensitizing. Furthermore, it is demonstrated that the optimum energy gap between the triplet state of ligand H6L1 and the emissive level of Tb3+ ion mak...

FCC high- and medium-entropy alloys (HEAs and MEAs) have demonstrated high ductility and fracture toughness, but suffer from low strength. To overcome such strength-ductility trade-off, here, we present a strategy via the formation of a high density of nanoscale precipitates in an ultrafine-grained (UFG) FCC matrix. To realize this concept, we selected a cost-effective equiatomic CrFeNi MEA as our model system. The equimolar elemental powder mixture was first forced into the formation of a nanostructured supersaturated FCC solid solution, followed by densification via spark plasma sintering (SPS). During SPS, a high density of nanoscale Cr-rich precipitates were formed in the UFG FCC matrix (821 nm). Such a particular microstructure enabled the alloy to overcome the strength-ductility trade-off, with a high tensile strength of 826 MPa and elongation of 26%. Grain boundary strengthening and precipitation strengthening were found to be the main strengthening mechanisms. These results provide deep insight into the design of novel multi-principal element alloys with high strength and ductility for structural applications.

All-inorganic cesium lead halide perovskite nanocrystals (NCs) with different dimensionalities have recently fascinated the research community due to their extraordinary optoelectronic performance such as tunable bandgaps over the entire visible spectral region. However, compared to well-developed 3D CsPbX3 perovskites (X = Cl, Br, and I), the bandgap tuning in 0D Cs4PbX6 perovskite NCs remains an arduous task. Herein, a simple but valid strategy is proposed to tailor the insulator bandgap (approximate to 3.96 eV) of Cs4PbBr6 NCs to the blue spectral region by changing the local coordination environment of isolated [PbBr6](4-) octahedra in the Cs4PbBr6 crystal through Sn cation doping. Benefitting from the unique Pb2+-poor and Br--rich reaction environment, the Sn cation is successfully introduced into the Cs4PbBr6 NCs, forming coexisting point defects comprising substitutional Sn-Pb and interstitial Br-i, thereby endowing these theoretically nonluminescent Cs4PbBr6 NCs with an ultranarrow blue emission at approximate to 437 nm (full width at half maximum, approximate to 12 nm). By combining the experimental results with first-principles calculations, an unusual electronic dual-bandgap structure, comprising the newly emerged semiconducting bandgap of approximate to 2.87 eV and original insulator bandgap of approximate to 3.96 eV, is found to be the underlying fundamental reason for the ultranarrow blue emission.

Two 3D lanthanide frameworks, [Ln7(DPA)5(NA)3(μ3-OH)8(H2O)3]·2.5H2O [H2DPA = diphenic acid; HNA = nicotinic acid; Ln = Gd (1), Dy (2)], were synthesized and structurally characterized. They were rarely seen examples of 3D frameworks constructed from heptanuclear trigonal-antiprismatic lanthanide clusters with mixed H2DPA and HNA ligands. Both 1 and 2 show typical antiferromagnetic interactions. Additionally, complex 1 possesses a large magnetocaloric effect of 34.15 J kg(-1) K(-1).

A novel self-assembly system has been developed, in which Ag6L4 cages can not only effectively assemble into a polycatenane containing multiple mechanical bonds in their supersaturated (MeOH–CHCl3) solution in a kinetically-controlled way, but can also be directly linked into a highly ordered polycage in the unsaturated solution through a thermodynamically-controlled assembly process. Moreover, the newly-constructed multiple mechanical bonds can also be opened and transformed into metal–metal interactions through reconstruction of the kinetically-controlled product into the thermodynamically-controlled product in the (MeOH–CHCl3) system, while the more strongly polarised DMSO solution can only open these multiple mechanical bonds.

Self-assembly of Co(II)/Cd(II) with 4,4′-sulfonyldibenzoic acid and bis(4-pyridylmethyl)piperazine has produced 3D interpenetrated and non-interpenetrated polythreading networks with non-trivial linkages.

Pd nanoparticles have been successfully supported on nanoscale metal-organic frameworks (NMOFs) by using a simple and effective microwave-assisted impregnation process. The resulting composite, representing as a highly active NMOFs supported metal nanoparticles catalyst for the Suzuki cross-coupling reaction between aryl/heteroaryl halides and arylboronic acids, is well characterized, and its high activity and good recyclability are discussed in details. It reveals that, compared to the corresponding bulk MOFs and conventional active carbon materials, nanoscale MOFs as novel support materials for heterogeneous catalysts can exhibit superior performance in the catalytic reactions.

Formation of crystalline TiO 2 (anatase) films by anodic oxidation of titanium foils in ethylene glycol (EG) based electrolytes at room temperature has been investigated. By varying the anodizing parameters such as the amounts of water and NH 4 F added, applied voltage and anodization time, anodic TiO 2 films with different crystalline structures were obtained. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray powder diffraction (XRD) characterizations were employed to determine the morphologies and crystalline structures of as-prepared anodic TiO 2 films. The results indicate that crystallization of anodic TiO 2 films was generally facilitated by high fluoride concentration, high applied voltage and longer anodization time, and the formation of anodic TiO 2 films with best crystallinity could only be achieved when optimized amounts of water were added.

A new multistimuli-responsive luminescent material, [Cu8I8(4-dpda)6]n (1) (4-dpda=4-(diphenylphosphino)-N,N-dimethylaniline), has been obtained by combining inorganic Cu8I8 clusters and organic ligands 4-dpda, providing a novel in-/organic hybrid approach as an interesting alternative to all-organic approaches. Compound 1 responds well to thermo and mechanical force independently with color change due to the fact that the stimuli affect frontier molecular orbital and molecular packing modes, respectively.

Reactions of the semirigid polycarboxylate ligand, 2-aminodiacetic terephthalic acid (H4adtp), with Zn(II) and Cd(II) salts resulted in {[Zn2(adtp)(H2O)2]·2H2O}n (1) and [Cd2(adtp)(μ2-H2O)(H2O)3]n (3), respectively. By introducing auxiliary ligand 4,4′-bipyridine (bpy), two 3D regularly arranged pillared-layered frameworks {[Zn3(adtp)(bpy)1.5(μ3-OH)(H2O)]·NO3·3H2O}n (2a) and {[Cd4(adtp)2(bpy)(H2O)4]·2.5H2O}n (4) were obtained. Complex 1 is characterized as a two-dimensional (2D) layer structure, whereas complex 3 features a three-dimensional (3D) framework with two types of alternately arrayed channels. In complex 2a, the one-dimensional (1D) zinc chains built up of alternately interlinked tetranuclear and dinuclear units are cross-linked into 2D layers, which are further pillared by bpy into a 3D cationic framework with NO3− as counterions. As for 4, a 3D pillared-layer framework is observed and comprises carboxylic μ2-O bridged –M–O–M– chains. The auxiliary ligand bpy exerts a structure-directing effect on the resultant 3D pillared-layer architectures in 2a and 4, wherein μ3-OH bridged tetranuclear metal units or carboxylic μ2-O bridged –M–O–M– chains appear. Additionally, the cationic framework in 2a is strongly dependent on counter anions and the concentration of bpy ligand. The isomorphic {[Zn3(adtp)(bpy)1.5(μ3-OH)(H2O)]·ClO4·3H2O}n (2b) with ClO4− as template and counterions is also obtained. The luminescent properties of 1, 2a, 3 and 4 are investigated in detail. Compared with free H4adtp, complex 3 exhibits a larger blue-shifted emission band. Complex 2a displays tunable photoluminescence by variation of excitation light and temperature due to multi-centers emissions.

A temperature and anions induced coordination-driven self-assembly system based on dynamic Ag6L4 metallocage has been developed. Induced by SbF6- anions, both of kinetic-control [Ag3L2(SbF6)3]n and thermodynamic-control [Ag2L2(SbF6)2]n can be reassembled from discrete Ag6L4(SbF6)6 metallocages at 30 ℃, raising temperature up to 40 ℃ results to selective inhibition of their kinetic product. While driven by BF4- anions, dynamic Ag6L4(BF4)6 metallocages prior to self-assemble into thermodynamic-control polycage at 25 ℃, lowing the temperature down to 0℃ leads to selective inhibition of their thermodynamic product. which represents that both of kinetic-control assembly process and thermodynamic-control assembly process in a dynamic system can be selectively controlled driven by suitable external stimuli.

We demonstrate that three flexible MOFs termed FJI-H11-R (FJI-H=Hong's group in Fujian Institute of Research on the Structure of Matter, R=Me, Et, (i) Pr) can reversibly respond to temperature and solvents via structural transformations, which can be visualized by in situ single-crystal X-ray snapshot analyses. FJI-H11-R exhibit colossal anisotropic thermal expansion, with a record-high uniaxial positive thermal-expansion coefficient of 653.2×10(-6) K(-1) observed in FJI-H11-Me. Additionally, large c-axial shrinkage of 32.4 % is also observed during desolvation. The stimuli-responsive mechanism reveals the structural evolutions are related to the rotations and deformations of the organic linkers.

Five metal–organic coordination polymers constructed from tris(p-carboxylphenyl)phosphine oxide (TPO), namely, [Ni3(TPO)2(2,2′-bipy)2(H2O)6]n·2nH2O (1), [Ni3(TPO)2(phen)2(H2O)6]n·2nH2O (2), [Ni3(TPO)2(bpe)3(H2O)8]n·4nH2O (3), [Mn(TPO)(2,2′-bipy)(H2O)]n·nH2O (4) and [Mn(BPO)(phen)]n (5) (BPO = bis(4-carboxylphenyl)phosphinic acid, bpe = trans-1,2-bis-(4-pyridyl)ethylene, 2,2′-bipy = 2,2′-bipydine, phen = 1,10-phenanthroline), were hydrothermally synthesized and determined by single-crystal X-ray diffraction analyses. Both of the bpy and phen ligands tailor the NiII complexes 1 and 2 into the ladder-like 1D chain geometries, while the bpe as a bridging ligand leads the NiII complex 3 to form a 2D plane geometry. It is interesting to find that the 2,2′-bipy and phen play a different role in the construction of MnII complexes 4 and 5; where complex 4 crystallizes in a chiral P212121 space group, while a new BPO ligand is formed from the in situ reaction of TPO in 5. Each P O group of BPO in 5 links with two MnII ions leading to new [Mn2(PO)2] cluster, and the clusters are bridged by four BPO ligands to give a ring-like structure.

Two novel coordination polymers [Ca4(C4AS)2(μ3-2,2′-bpno)•15H2O]n•2nH2O (1) and [Cu(H2O)6]n•[Cu2(TC4AS)(μ-2,2′-bpno)•3H2O]n•10nH2O (2) (C4AS=p-sulfonato-calix[4]arene, TC4AS=p-sulfonatothiacalix [4]arene and 2,2′-bpno=2,2′-bipyridine-1,1′-dioxide) have been synthesized and characterized. X-ray diffraction analyses reveal that the rail-like chains of 1 composed of bicapsule units in upper-to-upper way are parallel to the bilayers of 1, whereas the zigzag-like chains of 2 made up of capsules via upper-to-lower mode run through the bilayers of 2. The magnetic properties of complex 2 were examined, indicating weak ferromagnetic interactions between the copper(II) ions in the temperature range of 20–300 K.

Complexes [Zn(bpdc)(H2O)2] (1) and [Mn(bpdc)(H2O)3]∙2.5H2O (2) were assembled by 2,2′-bipyridine-6,6′-dicarboxylate (H2bpdc) with Zn2+ or Mn2+ under hydro/solvo-thermal conditions. Complexes 1 and 2 are extended from mononuclear to 1D, 2D and 3D supramolecular network step by step with the help of intramolecular weak interactions. The luminescent properties of 1 had been investigated in details, which show intense blue emission with relatively good quantum yield. The 2 displays nonlinear optical (NLO) activity comparable with that of KDP, and exhibits weak antiferromagnetic coupling between the Mn (II) ions by the hydrogen bonds.

Solvothermal reactions of thiacalix[4]arene, NaN3, and acetonitrile in the presence of nickel(II)/cobalt(II) salts yielded four discrete complexes sustained by the in situ generated 5-methyltetrazolate ligand, [NiII12(PTC4A)3(μ6-CO3)2(μ-Mtta)2(μ-Mtta)4 (μ4-Mtta)2(Py)4]·7DMF·2Py·dma (1), [CoII12(PTC4A)3(HCOO)3(μ6-CO3)2 (μ-Mtta)(μ-Mtta)2(μ4-Mtta)2(Py)4]·5DMF·dma (2), [CoII12(BTC4A)3(HCOO)2 (μ6-CO3)2(μ-Mtta)4(μ4-Mtta)2(dma)2(Pz)2]·2DMF·3dma (3), and [CoII16(BTC4A)4(μ4-Cl)4 (HCOO)2(μ-Mtta)6(μ-Mtta)8]·10DMF·6CH3CN·4Hdma (4) (H4PTC4A = p-phenylthiacalix[4]arene; H4BTC4A = p-tert-butylthiacalix[4]arene; HMtta = 5-methyl tetrazolate). Crystal structural analyses revealed that complexes 1–3 are stacked by pseudotrigonal planar entities, which consist of three metalII4-thiacalix[4]arene subunits including two shuttlecock-like and one cylinder-like ones. These subunits are connected in an up-to-down-to-up fashion through six different 5-methyl tetrazolate anions. Both the in situ generated 5-methyl tetrazolate anion...

Four indium(III)-biphenyl carboxylate coordination complexes: [In(dpdc)(bipy)Cl]2 (1), {[In(Hdptc)(bipy)]2·H2O}n (2), [In(dptc)·H3O]n (3), [In3(μ2-OH)2(Hdptc)(dptc)H2O]n (4) (H2dpdc = diphenyl-2,2′-dicarboxylic acid, bipy = 2,2′-bipyridine, H4dptc = biphenyl-2,2′,6,6′-tetracarboxylic acid) have been synthesized under hydrothermal and solvothermal conditions. Complex 1 exhibits a dimeric molecule structure featuring a square motif organized by two In(III) ions and two dpdc ligands each at the corner; 2 contains a similar dimeric segment which is extended into a 1D ribbon structure by the Hdptc ligands and further assembled into 2D supramolecular layer through hydrogen bonding; 3 features a 2D (4,4) grid layer, which is assembled into 3D supramolecular network through hydrogen bonding with guest water molecules. Complex 4 consists of an unprecedented eight-connected trinuclear In3(μ2-O)2(CO2)8 building unit which is jointed by four-connected dptc ligand into a binodal (4,8)-connected scu topology. The results present a feasible way of manipulation to control the dimensionality of the complexes by adjusting ligands and reaction temperatures. The complexes are also characterized by X-ray powder diffractions (PXRD), infrared spectroscopy and elemental analysis.

Reactions of a tripodal ligand, N,N',N″-tris(3-pyridinyl)phosphoric triamide (TPPA), and a series of transition-metal ions result in the assembly of five discrete M(6)L(8) coordination cages [M(6)(TPPA)(8)(H(2)O)(12)](ClO(4))(12)·57H(2)O [M = Ni(2+) (1), Co(2+) (2), Zn(2+) (3), Cd(2+) (4)] and [Pd(6)(TPPA)(8)]Cl(12)·22H(2)O (5). X-ray structural analyses reveal that the cages have large internal cavities and flexible windows. The flexible ligand TPPA adopts the syn conformation in cages 1-4, but it transforms to the anti conformation in cage 5. Because of the conformational transformation, the sizes of the windows and the volume of the internal cavity of cage 5 are increased. (1)H NMR and electrospray mass spectrometric studies show that cage 5 maintains its structural integrity in solution. Additionally, compounds 3 and 4 exhibit strong blue fluorescent emissions, which are 1 order of magnitude higher than that of the free ligand.

Solvothermal reactions of 2,2′-biphenyldicarboxylate (H2dpa) and 4,4′-azobispyridine (azpy) in the presence of transition metal ions produce six new complexes, namely, [Co(dpa)(bphy)]n (1), [Co(dpa)(azpy)(H2O)]n·0.5nH2O (2), [Zn(dpa)(bphy)]n (3), [Zn(dpa)(azpy)(H2O)]n (4), [Mn(dpa)(azpy)(H2O)]n·0.5nH2O (5), and [Mn(dpa)(azpy)]n·nH2O·nMeOH (6) (bphy = 1,2-bis(4-pyridyl)hydrazine). The crystal structure analyses reveal that complexes 1 and 3 are isostructural which features a plywood-like structure, while complex 4 exhibits a parallel chains array. Complexes 2 and 5 afford a two-dimensional chiral (4,4) network, and complex 6 shows a (4,4) network. It was noteworthy that the in situ reduction of azpy to bphy was found in complexes 1 and 3, which were confirmed by single-crystal structures and LC-MS analyses. However, this in situ reduction was not found at a low reaction temperature in the syntheses of complexes 2, 4, and 5. The second-harmonic-generation (SHG) properties of 1 and 3 and the solid circular d...

From our recently reported [Ag2L2]2+ metallacyclic species (L = 2,5-bis(4-pyridinylmethylthio)-1,3,4-thiadiazole), four coordination networks [Ag2L2]n·2n(ClO4)·7nH2O (1), [Ag2L2]n·2n(BF4)·5nH2O (1a), [Ag2L2]n·n[Ag2L2]·4n(NO3) (2) and [AgL(NO2)]n (3) were synthesized under the different anion conditions, which can be classified into three distinct supramolecular structures. Complexes 1/1a are constructed by disilver(I) macrocyclic motifs with the chair conformation, whereas 2 consists of two types of boat-form metallacycles. In 3, the bridging L adopts an extended conformation in sharp contrast to that in 1/1a/2. In this system, conformations of the metallacyclic subunit and flexible ligand L are modulated by various counter anions. For weakly coordinating anions, anion-exchange results indicate that complexes 1/1a maintain the primary structures and have an affinity order in agreement with the Hofmeister series. It is noteworthy that when complexes 1/1a/2 are treated with an aqueous solution containing NO2−, they all undergo a fast and quantitative anion-exchange process to afford complex 3. This process accompanies remarkable conformational conversion of L from cis, cis, syn to trans, trans, syn form. Atomic force microscopy studies indicate a solvent-mediated rather than a solid-state mechanism for the anion exchange.

Treatment of bix (1, 4-bis(imidazole-1-ylmethyl)benzene) with AgI generated [(Ag4I4)(bix)]n 1, whose crystal structure reveals a 2D organic–inorganic layer formed by novel wave-like silver(I) iodide chains with the linkers of bix ligands. The layers are arranged in parallel with the mode of {ABAB…} type showing 1D rectangular channels. In solid state, 1 exhibits multiple emission properties originating from its different natures, while optical absorption spectrum suggests that 1 might be a potential wide-gap semiconductor.

Two coordination polymers, [Zn(PPA)2(H2O)2]n (1) and [Cd(PPA)2]n (2) (HPPA = 3-pyridinepropionic acid) have been hydrothermally synthesized. Both of 1 and 2 crystallize in P-1 space group. Zn(II) centers in 1 are extended by PPA ligands to form the 1D chains, which are consolidated by hydrogen bonding to construct a 3D supramolecular network. The structure of 2 represents a rare binodal (3,6)-connected 2D layer with kgd topology. The luminescent properties of 1 and 2 in the solid state are discussed.

A localized dielectric breakdown model with good universality is introduced to explain the pore initiation, separation and growth processes of nanoporous and nanotubular anodic metal oxides. It is suggested that the degree of localized dielectric breakdown, which is mainly determined by the dielectric strength and energy band gap of the anodic oxide, electrolyte used, anodizing field and also temperature during anodization, has a significant effect on the pore formation. Continuous nanoporous films tend to grow under low degree of localized dielectric breakdown of the anodic oxides, and the growth in number and size of voids induced by high degree of localized dielectric breakdown at the inter-pore areas leads to the separation of neighbouring pores and, therefore, formation of nanotubular structures. Specially, anodic TiO2 nanotubes are believed to grow by continuous localized dielectric breakdown and self-healing processes at the base of main pores. Alternating dielectric breakdown and oxidation processes at the inter-pores areas lead to the formation of commonly observed O-ring like ridges.

The MnII and CuII compounds of 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine-4,4′-disulfonic acid (H2pdtd) were synthesized and systematically characterized. The metal-organic framework (MOF) [Mn2(pdtd)2(H2O)4]n·5nH2O (1) was constructed by a solvothermal method preformed at 140 °C with methanol as the solvent, while [Cu(pdtd)(H2O)4]·H2O (2) was obtained by conventional solution chemistry conducted at 80 °C. Crystallographic analysis revealed that 1 has an acentric structure in which the MnII centers are linked via sulfonate groups and chelating nitrogen atoms within the pdtd ligands to give a rare noninterpenetrating (10,3)-d framework with permanent helical cavities. Consequently, 1 exhibits nonlinear optical (NLO) activity, significant CO2 sorption, and magnetic coupling. In contrast, 2 is a mononuclear complex with coordinated water and lacks functional properties.

Two novel compounds, [Zn(H2PIDC)2(H2O)2] (1) and [Zn4(PIDC)2(SO4)(H2O)5]·(2.5H2O) (2) (H3PIDC = 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic acid) have been synthesized under hydrothermal condition, and characterized by thermal analyses (TGA), powder X-ray diffractions (PXRD), and single-crystal X-ray diffractions, respectively. Compound 1 is constructed from mononuclear molecules which form the 2D square networks and further extend to 3D supermolecular framework through the π–π stacking and strong hydrogen bonding interactions. Compound 2 exhibits a 3D framework and generates the 1D open rhombic channels filled with the coordinated water molecules, sulfate anions and free water molecules. The structure of 2 can be rationalized as a (4,4,4)-connected net and shown as a unique (4.53.6.7)4(42.52.72)2(52.62.72) topology. The different luminescent nature for 1 and 2 may be due to their various delocalization environments.

Four nickel(II)-5-aminodiacetic isophthalate coordination polymers with different auxiliary ligands are synthesized by the solvothermal method. {[Ni4(adip)2(H2O)10]·6H2O}n (1) (H4adip = 5-aminodiacetic isophthalic acid) is a supermolecular structure assembled by two-dimensional (2D) layers, and it can be viewed as a novel binodal (3,4)-connected topological net with a Schlafli symbol of (4.6.8)4(62.82.102) which has not been reported in the literature. When dipyridyl auxiliary ligands with different spacers are engaged in the reactions to pillar the 2D layers of 1, the 3D frameworks of complexes 2–4 are obtained. {[Ni3(Hadip)2(bpy)2(H2O)4]·9H2O}n (2) (bpy = 4,4′-bipyridine) was crystallographically characterized to be a three-dimensional (3D) coordination network with SPC519 type topology. {[Ni8(adip)4(bpy)(H2O)18]·10H2O}n (3) as a 3D framework exhibits a scarcely reported (3,5)-connected topology with a Schlafli symbol of (4.6.8)4(62.86.102). {[Ni2(adip)(bpp)(H2O)2]·2H2O}n (4) (bpp = 1,3-bis (4-pyridyl)p...

A series of novel three-dimensional (3D) 3d-4f heterometallic coordination complexes, [{LnZn(bpdc)2(OAc)(H2O)2}·H2O]n (Ln = Nd (1), Sm (2), Eu (3), Tb (4), Dy (5), Er (6); H2bpdc = 2,2′-bipyridyl-4,4′-dicarboxylic acid; HOAc = acetic acid), have been successfully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. All complexes are isostructural and display new 2-fold interpenetrating (3,6)-connected network topology. The luminescent properties of 1–5 in the solid state at room temperature have been studied in detail. It is the first series of luminescent 3d-4f heterometallic complexes with bpdc2– ligands, and it has been found that the energy transitions from the ligands to Eu3+ and Tb3+ are more effective than those to Sm3+ and Nd3+, and the energy transition from the ligand to Dy3+ is in between. Furthermore, thermogravimetric analysis and powder X-ray diffraction are also investigated.

Tripodal host 2,4,6-tris(1-phenyl-1H-tetrazolylsulfanylmethyl)mesitylene (TPTM) has been synthesized through a facile procedure. As expected, it adopts an all-syn cylindrical configuration, thereby delimiting an inner cavity. To explore the solvatomorphism and inclusion behavior of TPTM, a series of organic and inorganic species were employed as guests to afford 17 inclusion compounds (1, 2, 3 a-3 f, 4 a-4 i) that can be classified into four distinct forms (forms I-IV), under similar conditions. These compounds were characterized by single-crystal and powder X-ray diffraction, and (1)H NMR studies. In compound 1 with form I, one foot of a TPTM molecule inserts into the cavity of an opposite TPTM molecule to form a dimeric "hand-shake" motif with one acetonitrile molecule occupying the void. Compound 2 with form II contains three types of capsule-shaped dimers, each of which holds a CH(2)Cl(2) molecule as the guest. In compounds 3 a-3 f with form III, each pair of TPTM molecules interdigitates to form a capsule-shaped dimeric unit accommodating a guest molecule in the endo-cavity. In compounds 4 a-4 i with form IV, each TPTM molecule makes contact with three nearby TPTM molecules in a "self-including" manner to generate a graphite-like organic layer, and through further superposition to form open hexagonal channels. From the experimental and theoretical results, the intrinsic properties of guest molecules, such as size, shape, and self-interaction, can be regarded as the main factors leading to these solvatomorphism phenomena and the subtle inclusion behavior of TPTM. Thermogravimetric analyses show that the encapsulated guest molecules in these compounds can be evacuated at relatively high temperatures, and this demonstrates the outstanding inclusion capability of TPTM. In addition, for compound 4 a with benzene molecules in the channels, reversible exchange of toluene and separation of xylene isomers on single crystals have been observed.

Five Mn II -sdba coordination polymers with mono-, di-, tri-, tetra-nuclear cores based on the V-shaped 4,4′-dicarboxybiphenyl sulfone (H 2 sdba) ligands: [Mn(sdba)(phen) 2 (H 2 O)] n ·3 n H 2 O ( 1 ), [Mn 2 (sdba) 2 (μ-H 2 O)(py) 4 ] n ( 2 ), [Mn 3 (sdba) 2 (Hsdba) 2 (2,2′-bipy) 2 ] n ( 3 ), [Mn 4 (sdba) 4 (4-mepy) 2 (H 2 O) 4 ] n ·2 n H 2 O ( 4 ) and [Mn 4 (sdba) 4 (bpp) 4 (μ-H 2 O) 2 ] n ·0.5 n H 2 O ( 5 ) (phen = 1,10-phenanthroline, 2,2′-bipy = 2,2′-bipyridine, 4-mepy = 4-picoline, bpp = 1,3-bi(pyridine-4-yl)propane) were hydrothermally synthesized and structurally characterized. The M–O–C metal clusters in above complexes act as SBUs, and the V-shaped sdba ligands link the SBUs to generate the novel frameworks. In complexes 1 and 3 their 1D chains are linked into the 2D planes through various hydrogen bonding. Complex 2 displays the 3D structure with interpenetrated threefold, while complexes 4 and 5 both exhibit the 3D structures with the tetra-nuclear Mn 4 units. The magnetic susceptibility studies in the 2–300 K range for these complexes reveal the existence of anti-ferromagnetic exchange interactions between the Mn II ions.

[Co3(1,2-S2C6H4)3(PPh3)3][CoBr3(DMF)]sol (1, sol=CHCl3·O(C2H5)2·H2O) was obtained from the reaction of CoBr(PPh3)3 with Na2(S2C6H4) in chloroform. The Co3 core in the cation of 1 exhibits a metal-metal bonded isosceles triangle, in which the two longer Co—Co bonds are both bridged by S2C6H4 ligands on two sides of the triangle plane respectively, while the bottom short Co—Co bond is bridged by the third bidentate S2C6H4 ligand. A series of polynuclear cobalt cluster compounds with phosphine, thiolate and/or sulphur ligands were prepared by low oxidation state Co+ with thiolates in organic solvents. These tri-, tetra-, hexa-, heptanuclear cluster compounds 1–8 with various types of crystal structures can be viewed as the condensed polynuclear cobalt complexes that the cobalt atom frameworks with sulphur bridged were built through the small triangular units of [Co3S3nL3] (n=1,2) with or without [CoL] (L=PR3, Br, Cl,5-C5H5) fragments.

[V2(μ-S2)2(S2CNEt2)4] 2CH3Cl was synthesized by the reaction of NaS2CNEt2, Li2S and VOCl3 at room temperature. Crystal data: M= 1061.3, space group Pbca, with the orthorhombic parameters: a=20.123(3), b = 20.485(4)1c=10.911(3)A, V=4497.7A3, Z=4, Dc=1.57 g/cm3, Mo Ko radiation (λ=0.71069 A), μ = 13.2 cm−1, F(000)—2168. Final R = 0.041 and Rw=0.047 for 2288 observed reflections with I>3σ(I). The coordination sphere of each V atom in title compound is a distorted tetragonal prism composed of two bidentate dithiocarbamate and two S21− ligands. The V—V distance is 2.890 A while the V—S distances fall in the range of 2.422–2.505 A.

Co4(μ3-S)8(Ph2PCH2sP(O)Ph2)6, MW = 3012.5, space group R3, has the hexagonal parameters, a = 26.764 (10), c = 16.979 (10) A, V = 10532.8 A3, Z = 3. Mo Ka radiation, λ = 0.71069 A, Dc = 1.425 g/cm3, μ = 9.94 cm−3, F(000) = 4650, R = 0.073 and Rw = 0.077 for 1965 observed unique reflections with I > 3σ (I). The molecular structure consists of a distorted octahedral Co4—core. The Co—Co and Co—S distances fall in the range of 2.805—2.838 and 2.213—2.253 A, respectively.