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The combination of ultraviolet (UV) light and H2O2 is generally considered a promising technology for removing atrazine from the aqueous environment due to its high degradation efficiency, but the ...

A facile and effective impregnation combined with photo-deposition approach was adopted to deposit cadmium sulfide (CdS) nanoparticles on CTF-1, a covalent triazine-based frameworks (CTFs). In this system, CTF-1 not only acted as supporter but also served as photocatalyst and electron donor. The performance of the obtained CdS deposited CTF-1 (CdS-CTF-1) nanocomposite was evaluated by H2 evolution reaction under visible light irradiation. As a result, CdS-CTF-1 exhibited high H2 production from water, far surpassing the CdS/CTF-1 nanocomposite, in which CdS was deposited via solvothermal method. The high activity of CdS-CTF-1 was attributed to the confined CdS nanoparticles with small size, leading to expose more active sites. In addition, time-resolved spectroscopy indicated that the superior performance of CdS-CTF-1 also can be ascribed to the fast electron transfer rate and injection efficiency (KET = 0.18 × 109 s−1, ηinj = 39.38%) between CdS and CTF-1 layers, which are 3.83 times faster and 4.84 times higher than that of CdS/CTF-1 nanocomposite. This work represents the first example on using covalent organic frameworks (COFs) as a support and electron-donor for fabricating novel CdS-COF nanocomposite system and its potential application in solar energy transformations.

In this study, nanoscale zero-valent iron (nZVI) with a considerably high surface area (182.97 m2·g−1) and featured morphology of chain structure has been synthesized and well characterized. The as-prepared nZVI on can totally remove Cr(VI) under anoxic condition after 20 min reaction, whereas only 43% of Cr(VI) was removed after 60 min reaction under oxic condition. Noteworthily, the nZVI exhibits excellent removal capacity of Cr(VI) (123.85 mg/g) and fast removal rate (0.017 g·mg−1·min−1), much better than those reported in the literatures except for that reported by Li et al. (2008) [1] . Experimental results have confirmed that only FeCr2O4 with low compactness was generated under anoxic and acidic conditions in the new process. And it is evident that the formation of the passivation layer which contains oxides and hydroxides (or (oxy)hydroxides) of iron and chromium were well hindered. Furthermore, the as-prepared nZVI has shown fast removal of traced Cr(VI) from the Cr-spiked drinking water or actual Cr-contaminated lake water. Accordingly, we proposed a new reaction process of Cr(VI) reduction by nZVI under anoxic condition. And we firstly make clear the detailed process of Cr(VI) removal by the as-prepared nZVI via X-ray photoelectron spectrometer (XPS) analysis in time scale. Meanwhile, the excellent Cr(VI) removal performance of the as-prepared nZVI could be attributed to (i) the high surface area, (ii) large quantity of active sites of nZVI, and (iii) fast electron transfer from the nZVI/FeCr2O4 to Cr(VI). The present work not only provides the potential materials for the application to the rapid and high-efficient removal of Cr(VI) from aqueous solution, but also proposed a new avenue for hindering the passivation of Fe0. And a detailed mechanism of the Cr(VI) removal by nZVI was proposed for the first time.

To solve serious energy and environmental crises caused by rapid industrial development, the formation of Z-scheme heterostructured photocatalysts is a promising approach for efficient and scalable H2 production from water splitting due to wide absorption range, high charge-separation efficiency and strong redox ability of the Z-scheme heterostructured photocatalysts. In this study, we combined the MOFs of NH2-MIL-125(Ti) with g-C3N4 functionalized by benzoic acid (CFB) to synthesize a novel composite catalyst of CFB/NH2-MIL-125(Ti) (CFBM) by covalent bonds for the first time. The benzoic acid in the CFBM acts as electron mediator to well separate photogenerated electrons and holes, leading to excellent photocatalytic performance of photocatalytic hydrogen generation from water splitting under visible light irradiation. Experimental results show that the H2 production rate of the 10CFBM is 1.123 mmol·h−1·g−1, which is about 6 times of the NH2-MIL-125(Ti). Meanwhile, the simple physical mixture of NH2-MIL-125(Ti) with 10 wt% g-C3N4 and the 10wt%g-C3N4/MOFs heterostructured catalyst all show much smaller H2 evolution rate and worse stability than that of the 10CFBM. Finally, we proposed a possible mechanism to well explain the improved photocatalytic performance of the Z-scheme photocatalytic system based on the results of different characterizations. The present work gives a good example to develop a novel Z-scheme heterostructured system with good stability and high photocatalytic activity for H2 evolution and puts forward a new synthetic strategy to prepare metal-free semiconductor/MOFs formed by covalent bonds.

Lissencephaly (LIS), denoting a "smooth brain," is characterized by the absence of normal cerebral convolutions with abnormalities of cortical thickness. Pathogenic variants in over 20 genes are associated with LIS. The majority of posterior predominant LIS is caused by pathogenic variants in LIS1 (also known as PAFAH1B1), although a significant fraction remains without a known genetic etiology. We now implicate CEP85L as an important cause of posterior predominant LIS, identifying 13 individuals with rare, heterozygous CEP85L variants, including 2 families with autosomal dominant inheritance. We show that CEP85L is a centrosome protein localizing to the pericentriolar material, and knockdown of Cep85l causes a neuronal migration defect in mice. LIS1 also localizes to the centrosome, suggesting that this organelle is key to the mechanism of posterior predominant LIS.

An alternative approach to fabricate color-tunable and white-light-emitting lanthanide(III) coordination polymers (LnCPs) is demonstrated by employing a selective light-emitting tetrazolate–dicarboxylate ligand, which displays different color emissions when coordinated to different lanthanide(III) ions. The emission colour of the obtained LnCPs can be modulated from orange to white by simply adjusting the excitation wavelengths. White-light emissions, with high color rendering index and favorable correlated color temperature, have been successfully realized in new 2D single-component Sm(III) and two-component Eu(III)-doped Gd(III) coordination polymers excited at specific excitation wavelengths.

Covalent triazine-based frameworks (CTFs), as a type of 2D conjugated polymer, have attracted keen attention because of the promising visible-light-driven photocatalytic performance for water splitting. Nonetheless, amelioration on the configuration and electronic microstructure of CTFs for enhanced photocatalytic performance is still challenging and anticipated. Herein, we developed a new strategy to synthesize visible-light-driven Cl-intercalated CTF-1 photocatalysts (labeled as Cl-ECF) via a ball-milling exfoliation-assisted acidification method. Many characterizations confirm the formation of Cl-C and Cl-N bonds in the Cl-ECF. The effects of the Cl-intercalation on the crystal structure, microstructure and charge transfer behaviors of CTF-1 were systematically studied by various characterizations and DFT calculation. The results revealed that Cl-ECF exhibited significantly promoted charge transfer, narrowed bandgap and enhanced photocatalytic activity of H2 production because Cl-C and Cl-N covalent bonds can form covalently interlayer channels in the Cl-ECF. The as-prepared Cl-ECF shows a hydrogen production rate of 1.296 mmol·g–1 h–1 under visible light irradiation, which is 2.2 times higher than that of CTF-1. This work could provide new insights into the new approach of intercalation modification to improve photocatalytic performance of 2D layered photocatalysts.

Herein, we report a novel high-dimensional I3O3 organic–inorganic hybrid framework, namely [Cd3(OH)2(tza)2]n (1) (H2tza = 1H-tetrazolate-5-acetic acid), where a rare pure ths inorganic connectivity of Cd–Ohydroxyl is observed. Meanwhile, 1 displays blue emission and high thermal stability up to 370 °C.

Ionothermal reaction of NiCl2·6H2O and tetrazole-1-acetic acid (1-Htza) in ionic liquid [BMIM]Br (BMIM = 1-butyl-3-methylimidazolium) afforded a new 3D Ni(II) coordination polymer [Ni(1-tza)2]n 1. When 2,2′-bipy was introduced, another 1D chained polymer, [Ni(1-tza)(2,2′-bipy)(H2O)2]nXn·2nH2O (2, X = 0.78Br + 0.22Cl) was acquired. Both compounds have been structurally characterized by single-crystal X-ray diffraction analyses. In the obtained compounds, 1-Htza ligands adopt two different coordination modes: μ3-κN4:κO1:κO2 for 1, and μ2-κN4:κO1 for 2. The temperature-dependent magnetic susceptibilities of 1 and 2 have been measured and theoretically fitted by means of a 1-D chain model. A ferromagnetic interaction between Ni(II) ions exists in 1 with J = 3.24 cm− 1, while an antiferromagnetic interaction in 2 with J = − 5.72 cm− 1.

Reaction of tetrazole-1-acetic acid (1-Htza) with a Cu(II) salt in ionic liquids with different anions, [BMIM]X (BMIM = 1-butyl-3-methylimidazolium; X = Br−, BF4−, NTf2− (NTf2− = bis((trifluoromethyl)sulfonyl)amide)), afforded five Cu(II) coordination compounds, [Cu2(1-tza)4]Br·H3O·1/3H2O (1), [Cu2(1-tza)4]BF4·H3O·H2O (2), [Cu(μ2-Cl)(1-tza)(1-Htza)(H2O)]·0.5H2O (3), [CuCl(μ2-Cl)(1-Htza)2(H2O)]·H2O (4), and [CuCl2(1-Htza)2]·H2O (5). Single-crystal X-ray diffraction analyses reveal that 1–5 display various structures, and the 1-tza− ligand exhibits diverse coordination modes. Compounds 1 and 2 possess higher dimensional structures (a 2-D neutral Kagome topology network for 1 and a 3-D lvt-type topology framework for 2) with fully deprotonated 1-tza− ligands. Compounds 3–5 display lower dimensional structures (1-D, 1-D and 0-D for 3, 4 and 5, respectively) with partly or fully protonated 1-Htza. The anions of ionic liquids have significant influences on the final molecular architectures, which arise from different water miscibility of ionic liquids.

The aqueous solution reaction of chelidamic acid (H3CAM), succinic acid, CdCl2·2.5H2O in the air at 50 °C, along with little of ammonia added dropwise, gave rise to colorless crystals {Cd2.5(CAM)(HCAM)(H2O)7·1.5H2O}n (1), which presents an interesting (4,6)-connected 3D structure. Notably, 1 is the third homonuclear 3D framework based on H3CAM ligand, which acts as two different μ4/μ5-bridges in 1 and was abbreviated to HCAM2 − and CAM3 −, respectively, in writing molecular formula of 1. Polymer 1 exhibits strong blue photoluminescence at room temperature.

Reactions of achiral 5-(3-pyridyl)-isophthalic acid (H2L) with Co2+ and Ni2+ under solvothermal conditions yield two new homochiral helical coordination polymers [Co(L) (H2O)2]n (1), [Ni(L) (H2O)2]n (2). Single crystal X-ray diffraction analyses show that complexes 1 and 2 are isomorphous with infinite 3D structures and they both contain two enantiomers, 1a and 1b for Co and 2a and 2b for Ni, crystallizing in the chiral hexagonal space groups P65 and P61, respectively. The enantiomeric nature of them is confirmed by the results of CD spectra. The optical properties of them were investigated in terms of diffuse reflectance, IR and fluorescent spectra, which both exhibit strong luminescence. The electronic band structure along with the density of states (DOS) calculated by the DFT method indicate that compound 1 pose an energy band gap of 3.58 eV and that the origin of the emission band may be mainly ascribed to charge transfer (ILCT) where the charges are transferred between the O-2p state and C-2p state.

Through controlling the temperature, pH value, solvent and added metal salts, six new zinc(II) and cobalt(II) coordination polymers with different structural features, formulated as {[Zn2(HCAM)2(bipy)]·2H2O}n (1), {[Co3(CAM)2(bipy)2·(H2O)4]·16/3H2O}n (2), {[Co(HCAM)(bipy)]·19/6H2O}n (3), {4(H2O)·[Co(bipy)·(H2O)4](bipy)[Co(HCAM)2]}n (4), Zn2(HCAM)2(bipy)·(H2O)2 (5), and 2(H2O)·[Co2(HCAM)2(bipy)·(H2O)4] (6) (bipy = 4,4′-bipyridyl), have been synthesized based on reaction between chelidamic acid (2,6-dicarboxy-4-hydroxypyridine, called as H3CAM) and 4,4′-bipyridyl. For 1 and 3, metal ions connected by the carboxylate O atoms to form a one-dimensional chain, which was then further linked by 4,4′-bipyridyl to form 2D coordination polymers. In 2, the Co(II) ions and chelated chelidamic acid ligands are interconnected by the hydroxyl oxygen atom to form a nearly linear chain and are further assembled into a 2D coordination polymer via the [Co(bipy)2·4H2O]2+ units. In 4, there exist a one-dimensional polymeric [Co(C10N2H8)·(H2O)4]n2+ chain and a discrete [Co(HCAM)2]2− anion, and then further assemble into a 2D supramolecular network via H-bonds and π–π stacking interactions. And compounds 5 and 6 are isostructural and possess discrete structures. The solid-state photoluminescence, magnetic properties and IR of 1–6 have been investigated.

A novel one-dimensional (1-D) mixed-valent thioarsenate (III, V), {[Mn(phen)]3(AsVS4)(AsIIIS3)}n·nH2O (1), with a noncentrosymmetric (NCS) polar packing arrangement has been obtained under solvothermal conditions. The noncondensed (AsIIIS3)3– anion in 1 is stabilized by coordinating to [MnII(phen)]2+ complex cations and exhibits an unprecedented μ3-1,2κS:2,3κS′:3κS′′ linkage mode. Compound 1 represents the first example of the stabilization of noncondensed (MQ3)3– (M = As, Sb; Q = S, Se) species only in the coordination of TM(II) complex cations (TM = transition-metal) and the first observation of the coexistence of the (AsVS4)3– tetrahedron and the noncondensed (AsIIIS3)3– pyramid in a single compound. Of particular interest, compound 1 is also an antiferromagnet with TN = 31 K, and exhibits photoluminescence (PL) with a maximum emission at about 438 nm and a second harmonic generation (SHG) response.

Hydrothermal reaction of NaN3, Na(4-cba) (4-Hcba = 4-cyanobenzoic acid) and ZnBr2 afforded a novel 3D Zn(II) coordination polymer [Zn2(4-tzba)2(H2O)]n 1 (4-H2tzba = 4-(5H-tetrazol)benzoic acid). In situ [2 + 3] cycloaddition reaction of nitrile and azide in the presence of ZnBr2 yielded tetrazolate-5-carboxylate 4-tzba2− ligand. Compound 1 displays an unprecedented four-connected topological network with 1D hexagonal channels constructed from trigonal rings [Zn3(4-tzba)6]. The solid-state photoluminescent studies revealed that 1 exhibits a strong blue emission mainly originating from 4-tzba2− ligand-centered charge transition.

Reaction of lanthanide oxides and 1H-tetrazolate-5-ethyl formate in water at 50 °C in the presence of pyridine afforded a series of lanthanide coordination polymers, {(Hpy)2[Pr4(tzf)7(H2O)11]·10H2O}n (1) and {[Ln2(tzf)3(H2O)6]·4H2O}n, where Ln = Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Hpy = protonated pyridine, and H2tzf = 1H-tetrazolate-5-formate acid. Polymer 1 features a three-dimensional (3-D) anion framework built up by cross-linkage of tetrameric [Pr4(tzf)4]4+ units and tzf2− ligands, showing a six-connected primitive cubic (pcu) topology (412·63). Isomorphous polymers 2−6 present a two-dimensional (2-D) neutral structure with a four-connected (4,4) topology. Four new coordination modes of the tzf2− ligand are first observed in tetrazolate-5-carboxylate complexes. The lanthanide contraction effect and coordination flexibility of tzf2− ligand play a key role in governing the formation of coordination polymers with different polymeric architectures. The photoluminescent analyses for 2, 3, 5, and 6 sug...

Hydrothermal reaction of Na(3-cba) (3-cba = 3-cyanobenz-oate), NaN 3 and a metal salt with either 2,2'-bipyridine (2,2'-bipy) or 1,10-phenanthroline (phen) afforded four novel Zn II / Cd II polymers, which have been structurally characterized by single-crystal X-ray diffraction analysis. In situ [2 + 3] cycloaddition reaction of nitrile and azide in the presence of a Zn II or Cd II salt yielded the ligand 3-(5H-tetrazolyl)benzoate (3-tzba 2- ) [3-H 2 tzba = 3-(5H-tetrazolyl)benzoic acid]. The obtained polymers are formulated as [Zn 2 (3-tzba)(N3 ) (OH)(2,2'-bipy)](1),[Zn(3-tzba)(2,2'-bipy)(H 2 O)]·3H 2 O(2), [Zn 2 (3-tzba) 2 -(phen) 2 ]·H 2 O (3) and [Cd 4 (3-tzba) 2 (N 3 ) 4 (2,2'-bipy) 3 ]·H 2 O (4). A crystalline mixture of Zn II polymers 1 and 2 with infinite ladder-like chain and zigzag chain structures, respectively, was obtained from the reaction in the presence of 2,2'-bipy. The replacement of 2,2'-bipy with phen as an auxiliary ligand yielded 3, which shows a pearl-necklace-like chain structure. Further, the introduction of Cd II instead of Zn II resulted in the formation of 4, which has a 2D corrugated layer structure. The 3-tzba 2- ligands display four different coordination modes in 1-4, and modes μ 2 -κN2:κO1,O2 (in 2) and μ 3 -κN3:κO1:κO2 (in 3) are observed in tetrazolate-5-carboxylate polymers for the first time. Photoluminescent studies in the solid state at room and low temperature revealed that 1-4 exhibit interesting luminescent behaviors, and the relevant density of states (DOS) calculation results showed that their photoluminescence mainly originates from ligand-centered emission and is dependent on the organic ligand incorporated into the polymer.

A new approach has been used to synthesize MQ+ ligand (MQ+ = N-methyl-4,4′-bipyridinium) by the reaction of 4,4′-bipyridine and chloroacetic acid, and the structure of (MQ)Cl·H2O ( 1 ) was first determined. Three new complexes containing MQ+, (MQ)CdI3 ( 2 ), (MQ)ZnI3 ( 3 ), and [(MQ)ZnCl1.53I1.47]2(MQ)ZnCl1.68I1.32 ( 4 ), were successfully obtained via a solution or hydrothermal method by reaction of MI2 (M = Cd, Zn) with 1 , and each of which exhibits an isolated structure, with each metal atom coordinated by one MQ+ ligand and three terminal halogen atoms. Compounds 1 2 3 – 4 all display photoluminescence in the visible region under visible-light excitation, and the origins of the emissions have been assigned to ILCT for 1 and the combination of ILCT and LLCT for 2 3 – 4 .

Hydrothermal reaction of Cd(NO3)2, Co(NO3)2, Na(3-cba) and NaN3 yielded a 3D heterometallic coordination polymer, [Cd(μ5-3-tzba)(μ2-3-cba)(μ3-OH)Co(H2O)]n·2nH2O 1 (3-H2tzba = 3-(5H-tetrazol)benzoic acid and 3-Hcba = 3-cyanobenzoic acid), which was characterized by single-crystal X-ray diffraction. The in situ [2 + 3] cycloaddition reaction of nitrile and azide in presence of Cd(II) salt afforded tetrazolate-based 3-tzba2− ligand. In 1, metal-oxo chains [Cd(μ3-OH)Co]n are linked by 3-tzba2− in an unprecedented μ5-κN1:κN2:κN3:κN4:κO1,O2 coordination mode to form 2D layers, which are further pillared by 3-cba− to generate a 3D open framework encapsulating 1D chiral channels. Variable-temperature magnetic studies show that 1 exhibits antiferromagnetic interactions between Co(II) ions bridged by μ3-OH group.

Hydrothermal reaction of 1H-tetrazolate-5-ethyl acetate (Htzea), MCl2 (M = Zn, Cd) and NaOH at different reaction temperatures produced three new coordination polymers: 2-D layered polymer [Zn(tza)(H2O)2]n 1, and 1-D chained supramolecular isomers 2 and 3 formulated as [Cd(tza)(H2O)2]n (H2tza = 1H-tetrazolate-5-acetic acid), respectively. In these obtained polymers, tza2− ligand adopts variable coordination modes: μ3-κN3:κO1:κO2,N1 and μ3-κN1:κN3:κO2 for 1, and μ3-κN2:κN1,O2:κO1,O2 for 2 and 3. The effects of reaction temperature and metal centers on the final polymeric frameworks have been discussed. Polymers 1–3 exhibit blue photoluminescence mainly arising from intraligand transitions of tetrazolate rings in tza2− ligand.

Two bifunctional 1H-tetrazolate-5-carboxylate ligands with different flexibilities, H2tza (1H-tetrazolate-5-acetic acid) and H2tzf (1H-tetrazolate-5-formic acid), were employed in the construction of zinc(II) complexes in the presence/absence of secondary ligands such as 2,2′-bipy and 4,4′-bipy. Three tza coordination polymers and two tzf dinuclear complexes, namely [Zn(tza)(H2O)]n (1), [Zn3(tza)2Cl2(2,2′-bipy)2(H2O)2]n (2), [Zn2(tza)2(4,4′-bipy)]n (3), [Zn(tzf)(H2O)3]2·2H2O (4) and [Zn(tzf)(2,2′-bipy)(H2O)]2·H2O (5), were hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Polymer 1 is a 3-D two-fold interpenetrating diamond-like network with tetranuclear [Zn(COO)]4 clusters as tertiary building units (TBUs) and µ3-κN3:κO2:κO1,N1 bridging tza as linkers. Polymer 2 presents a 2-D structure formed by the linkage of 1-D Zn-carboxylate [Zn(COO)]n helical chains and µ3-κN4:κO2:κO1,N1 bridging tza. In 3, 2-D (4,4) nets are built up with dinuclear [Zn(COO)]2 clusters and µ3-κN4:κO2:κO1,N1 bridging tza, which are pillared through 4,4′-bipy to gain a 3-D self-penetrating LB-1 (446108) topology. In dinuclear complexes 4 and 5, two Zn(II) atoms are bridged by a tzf ligand in a µ2-κN2:κO1,N1 fashion. The results denote that tetrazolate-5-carboxylate ligands can adopt variable coordination modes in the formation of the complexes, and different Zn-carboxylate aggregates can serve as tertiary building units (TBUs). The effects of the nature of tetrazolate-5-carboxylate ligands and secondary ligands, and hydrothermal reaction conditions on the structural topologies of the obtained complexes have been investigated. The photoluminescent properties and thermal stabilities of 1–5 have also been discussed.

A series of rare-earth zirconium chalcogenides Ln(2)ZrQ(5) (Ln = La, Sm, Gd; Q = S, Se) synthesized by using boron as the reducing reagent show unprecedented single-crystal's intrinsic voltage-dependent effects and order antiferromagnetically.

A novel one-dimensional (1-D) mixed-valent thioarsenate (III, V), {[Mn(phen)](3)(As(V)S(4))(As(III)S(3))}(n)·nH(2)O (1), with a noncentrosymmetric (NCS) polar packing arrangement has been obtained under solvothermal conditions. The noncondensed (As(III)S(3))(3-) anion in 1 is stabilized by coordinating to [Mn(II)(phen)](2+) complex cations and exhibits an unprecedented μ(3)-1,2κS:2,3κS':3κS'' linkage mode. Compound 1 represents the first example of the stabilization of noncondensed (MQ(3))(3-) (M = As, Sb; Q = S, Se) species only in the coordination of TM(II) complex cations (TM = transition-metal) and the first observation of the coexistence of the (As(V)S(4))(3-) tetrahedron and the noncondensed (As(III)S(3))(3-) pyramid in a single compound. Of particular interest, compound 1 is also an antiferromagnet with T(N) = 31 K, and exhibits photoluminescence (PL) with a maximum emission at about 438 nm and a second harmonic generation (SHG) response.

The asymmetric unit of the title Cd(II) compound, [Cd(N(3))(2)(C(12)H(8)N(2))](n), contains a Cd(II) atom, located on a twofold axis passing through the middle of the phenanthroline mol-ecule, one azide ion and half of a 1,10-phenanthroline mol-ecule. The Cd(II) atom exhibits a distorted octa-hedral coordin-ation including one chelating 1,10-phenanthroline ligand and four azide ligands. The crystal structure features chains along the c direction in which azide groups doubly bridge two adjacent Cd(II) atoms in an end-on (EO) mode. Inter-chain π-π stacking inter-actions, with centroid-centroid separations of 3.408 (2) Å between the central aromatic rings of 1,10-phenanthroline mol-ecules, lead to a supra-molecular sheet parallel to the bc plane.

Background To investigate the association between metabolic syndrome, including its factors, and gallstone disease (GSD) in a Taiwanese population. Methods We conducted a cross-sectional study during 2011 ~ 2012. A total of 12050 subjects who completed a questionnaire and underwent physical examination, laboratory tests and abdominal ultrasonography formed the study population. Results The prevalences of metabolic syndrome and gallstone disease were 24.09% and 6.16%. In an age- and sex-adjusted logistic regression model, metabolic syndrome was associated with gallstone disease (OR = 1.61; P

Hydrothermal reaction of cyano-substituted viologen derivatives and NaN3 with corresponding metal salts in the presence/absence of H2PTA (H2PTA = p-phthalic acid) yielded three azide-based polynuclear coordination polymers: [Co4(N3)4(PTA)3(4-CV)2]n·2nH2O 3D (1), [Co4(N3)4(PTA)3(3-CV)2]n·nH2O 3D (2), and [Cu6(N3)14(4-CV)2]n 2D (3) (3/4-CV+ = 4,4′-bipyridinium-N-methyl-3/4-benzonitrile). The azido bridges are employed to construct two types of polynuclear cluster units: tetranuclear [Co4(μ1,1-N3)4] and hexanuclear [Cu6(μ1,1-N3)6(μ1,1,1-N3)4]. Polymers 1 and 2 are isostructural, and exhibit similar 3D frameworks constructed by unprecedented linear tetranuclear CoII4 units with a four-connected 65·8 topology. Polymer 3 features a 2D (4,4) topological network built up by hexanuclear CuII6 segments. The azide anion exhibits diverse coordination modes: μ1,1-N3 in 1 and 2, and μ1,1-, μ1,3-, μ1,1,1- and μ1,1,3-N3 in 3. Variable-temperature magnetic susceptibility data denote that 1 and 2 display a weak antiferromagnetic interaction in CoII4 units and 3 shows a dominant ferromagnetic exchange in CuII6 units.

Hydrothermal reaction of N-(2-cyanoethyl)glycine and NaN3 with corresponding metal salts yielded three energetic coordination polymers: [Zn(tzeg)]n1 and [M(tzeg)(H2O)]n (M = Cd2+ for 2, Cu2+ for 3) (H2tzeg = N-[2-(1H-tetrazol-5-yl)ethyl]glycine), which were characterized by single-crystal X-ray diffraction. Nitrogen-rich tzeg2− ligand is a new in situ generated organic compound through [2 + 3] cycloaddition reaction of nitrile and azide, which adopts two different coordination modes in 1–3. Polymer 1 features an achiral 3D network built up by interweaving of left/right-handed helical channels. Isostructural 2 and 3 exhibit an achiral 2D network formed alternately by left/right-handed helical chains. As nitrogen-rich energetic materials, 1 and 3 possess higher enthalpies of combustion (ΔHc), which are −12.054 and −11.583 kJ g−1, respectively, than the classical energetic compounds 1,3,5-trinitro-1,3,5,-triazine (RDX, −9.6 kJ g−1) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX, −9.44 to −9.88 kJ g−1). The solid-state excitation and emission spectra for 1–3 were investigated at room temperature, which reveals ligand-centered luminescent emissions in the intensity order of 2 > 1 > 3. Variable-temperature magnetic susceptibility data show that 3 displays a weak antiferromagnetic interaction mainly resulting from magnetic exchange coupling between Cu2+ ions through double tetrazolato bridges.

Four Zn(II) tetrazolate coordination compounds have been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction. They are formulated as [Zn(3-tzbd)2]n·nH2O (1), [Zn2(3-tzbd)2(OH)2(4,4′-bipy)]n·nH2O (2), [Zn2(3-tzbd)3(N3)(4,4′-bipy)2]n·nH2O (3) and Zn2(3-tzbd)4(phen)2 (4), where 3-Htzbd = 3-(5H-tetrazol)benzaldehyde. The 3-tzbd− ligand, which was in situ generated through a [2 + 3] cycloaddition reaction of nitrile and azide, displays diverse coordination modes. Compound 1 exhibits a (4,4)-connected two-dimensional (2D) layer generated by the linkage of dinuclear units of [Zn2(μ2-3-tzbd)2] and μ2-3-tzbd− ligands. In 2, Zn(II) atoms are connected by μ2-3-tzbd− ligands and μ3-OH− anions to form unusual double-stranded stair-like chains, which are further linked by 4,4′-bipy to create a 2D sheet. Compound 3 features an unprecedented one-dimensional (1D) four-legged, triple-ladder chain composed of tetranuclear units [Zn4(μ2-3-tzbd)4(μ2-N3)2]. Two Zn(II) atoms in 4 are bridged by μ2-3-tzbd− ligands to result in an isolated dinuclear structure. In addition, the luminescent properties of 1–4 were investigated in the solid state at room temperature. The relevant density of states (DOS) calculation results show that their photoluminescence mainly originates from ligand-centered emission and is dependent on the organic ligand incorporated into the compounds.

A new carboxylate-introduced 1,2,3-triazole, 1-(3,5-dicarboxyphenyl)-4-carboxy-1H-1,2,3-triazole (H3dcpct), was synthesized by 1,3-dipolar cycloaddition of a terminal alkyne to azide in the presence of a Cu(II) salt. Hydrothermal reaction of H3dcpct and Mn(NO3)2·6H2O or Co(NO3)2·6H2O in different NaOH/H3dcpct molar ratios afforded four new coordination polymers [Mn(dcpt)(H2O)2]·0.25H2O 1, [Mn(dcpt)(H2O)] 2, [Co(dcpt)(H2O)2]·H2O 3 and [Co(H2O)6][Co2(dcpct)2(H2O)6]·2H2O 4 (H2dcpt = 1-(3,5-dicarboxyphenyl)-1H-1,2,3-triazole). The in situ hydrothermal decarboxylation of H3dcpct into H2dcpt in 1–3 was found and its possible mechanism is proposed. In 1 and 3, dcpt2− ligands bridge Mn(II) and Co(II) ions, respectively, to give two similar 2D layered structures with a (6,3)-connected network topology. Polymer 2 displays a whole achiral 3D open framework with both chiral and achiral channels in the same direction and possesses an unprecedented (3,6)-connected (4·82)(42·812·10) network topology. The structure of 4 features a 1D chained net, in which no decarboxylation occurred. Variable-temperature magnetic susceptibility data show that 1 exhibits a weak ferromagnetic interaction and 2 manifests an overall antiferromagnetic interaction between their respective Mn(II) ions, while 3 and 4 display an antiferromagnetic interaction between Co(II) ions and/or spin-orbital coupling. The thermal stabilities of all obtained polymers have also been examined.

Hydrothermal reaction of ZnCl2, NCCH2CH2COONa and NaN3, in the absence/presence of auxiliary ligand 2,2′-bipy/4,4′-bipy, gave birth to three novel coordination polymers, namely, [Zn(tzp)]n (1), [Zn2(tzp)(N3)(OH)(2,2′-bipy)]n (2) and [Zn2(tzp)2(4,4′-bipy)]n (3) (H2tzp = 1H-tetrazolate-5-propionic acid). The tzp2− ligand was in situ generated through the [2 + 3] cycloaddition reaction of nitrile and azide, which was first untilized to synthesize coordination compounds. Polymer 1 behaves as a three-dimensional (3-D) network built up by the fusion of one-dimensional (1-D) pseudo-channels formed by the linkage of tzp2− ligands and tetrahedral Zn nodes. When the chelating 2,2′-bipy was introduced into the reaction system, a two-dimensional (2-D) puckered network 2 was constructed, where 1-D pseudo-channels, similar to those in 1, are bridged by azide ions in an end-on (EO) mode. Employment of the linear bridging 4,4′-bipy ligand as the auxiliary ligand resulted in the formation of an unusual 3-D polymer 3, where the connection of Zn and tzp2− produces a 2-D network, which are further joined by 4,4′-bipy. The tzp2− ligands in 1–3 show the flexible conformations and different coordination modes, with the tetrazolate group being the 1,4-N mode and the carboxylate group being the syn–anti, syn–syn and monodentate mode, respectively. The results suggest that the flexible nature of the tzp2− ligand as well as the introduction of auxiliary ligands is responsible for the formations of 1–3. Their photoluminescent properties and thermal stabilities have also been discussed.

The stabilization of the (SnS4)4− anion in the coordination of [Mn(phen)]2+ complexes brings about a novel compound {[Mn(phen)]2(SnS4)}n·nH2O (1), in which an unprecedented link mode of the (SnS4)4− anion is observed. Theoretical calculations indicate that TM complexes with big π-conjugated ligands, such as [Mn(phen)]2+, can serve as an excellent electron reservoir to stabilize the (SnS4)4− anion in 1, despite its strong condensation tendency. Magnetic measurements show the presence of strong antiferromagnetic interactions between the Mn2+ ions in 1.

Four new complexes with bifunctional tetrazolate-5-carboxylate ligands of 1H-tetrazole-5-formic acid (H2tzf) and 1H-tetrazole-5-acetic acid (H2tza), namely two dinuclear [M(tzf)(H2O)3]2·2H2O (M = Cu 1, Ni 2) and two mononuclear [Cu(tzf)(2,2′-bipy)2]·5H2O 3 and Cu(tza)(2,2′-bipy)H2O 4, were prepared and structurally characterized by single-crystal X-ray diffraction. Two different coordination modes of tetrazolate-5-carboxylate ligands exist: a tridentate N,O-chelated-N-bridged mode in 1 and 2, and a bidentate N,O-chelated mode in 3 and 4, which was first observed for the tetrazolate-5-carboxylate complexes. Extensive hydrogen bonds play an important role in the construction of the supramolecular network. Variable-temperature magnetic susceptibility data show the presence of antiferromagnetic interactions in 1 and 2. The thermogravimetric analyses of complexes 1–4 are also discussed.