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The ZrCuSiAs materials have many interesting physical properties and have been extensively studied in recent decades. Recently, two Mn-based ZrCuSiAs-type pnictides, i.e. ThMnAsN and ThMnPN, have been synthesized in the experiment, which shows the anti-ferromagnetic properties. Motived by the experiment, we here perform a comprehensive investigation on their elastic, electronic, and magnetic properties by the density functional theory and Monte Carlo simulations. Our calculations show that ThMnAsN and ThMnPN are both antiferromagnetic semiconductors. The magnetic ground state of both materials is the C -type anti-ferromagnetism and their bandgaps are about 0.47 eV and 0.61 eV for ThMnAsN and ThMnPN, respectively. The Monte Carlo simulated Néel temperatures of ThMnAsN and ThMnPN are 57 K and 55 K, respectively. These results are well consistent with the experimental results. Our work not only reveals the physical essence of the two newly synthesized materials but also could help to the understanding of the magnetic behaviors of other ZrCuSiAs-type compounds. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of disulfide-containing ligand 6,6′-dithiodinicotinic acid (H2cpds) with lanthanide metal salts led to three compounds {[Ln2(cpds)3(H2O)5]·7H2O} n (Ln=Gd, 1; Tb, 2; Er, 3) under hydrothermal conditions. The single-crystal X-ray diffraction analysis revealed that complexes 1–3 are isostructural. Two eight-coordinated metal centers are connected with carboxylate groups of H2cpds to give a binuclear [Ln2(CO2)4] unit. H2cpds discloses two independent binding modes resulting in the two types of 1-D chains by the connection of [Ln2(CO2)4] unit. Finally, the 1-D chains are linked by H2cpds to construct a 3-D network with an uncommon twofold interpenetrating 4-connected CdSO4 structure type (65,8 topology). It is worth noting that polyrotaxane-like motif is also exhibited in the 3-D network. The Tb(III) compound exhibits strong green photoluminescence in the visible region. Furthermore, the magnetic property of the Gd(III) compound has been investigated in the temperature range of 2–300K. The thermal behaviors and XPRD patterns of three compounds have also been discussed. [ABSTRACT FROM AUTHOR]

Abstract: Three new iron(III) citrate complexes [Fe2(cit)2(H2O)2](H2bpa) (1), [Fe2(cit)2(H2O)2](H2bpe) (2) and [Fe4(cit)4(H2O)4](H2bpp)2(H2O) (3) (cit=C(O−)(COO−)(CH2COO−)2, bpa=1,3-bis(4-pyridyl)ethane, bpe=1,3-bis(4-pyridyl)ethene, bpp=1,3-bis(4-pyridyl)propane) were synthesized and characterized by elemental analysis, spectroscopic techniques and magnetic properties. Single X-ray diffraction analyses in the 1–3 complexes reveal that the iron ion is six-coordinated and is bound by two deprotonated citrates and a pair of aqua ligands in a distorted octahedral fashion. The anionic complex contains a centro-symmetrical planar of four-membered Fe2O2 ring. There are significant contributions to the stabilities of the assembled lattices in 1–3 arising from the protonated pyridine analogue counterions neutralizing the anionic charges of the complexes. The units in the complexes are connected together via hydrogen bonding to form 3D supramolecular networks. The supramolecular structures of 1–2 show alternating and motif linking the anionic moieties which are in turn interwoven with cationic moieties, while 3 shows alternating and motif. The magnetic properties of 1–3 are investigated and discussed in detail. [Copyright &y& Elsevier]

A series of nickel dithiolene molecular crystals [Et3N(CH2)3X][Ni(mnt)2] (1: X = H, 2: X = Cl, 3: X = Br and 4: X = I and Br; mnt2− = maleonitriledithiolate) were prepared by introducing triethylpropylammonium derivatives (X–CH2CH2CH2–NEt3+) into [Ni(mnt)2]− building blocks. 1 crystallizes in a monoclinic system with the space group P21/n at 293 K, and the cations and anions in 1 are arranged in columnar segregated stacks along the a-axis direction. Crystals 2 and 3 also belong to monoclinic systems with space groups P21/n and P21/c, but 4 crystallizes in a triclinic system with the space group P1¯. Interactions between [Ni(mnt)2]− ions in all crystals are antiferromagnetic, and the magnitudes of the interactions are qualitatively consistent with the strength of intermolecular interactions estimated from transfer integrals, where interactions between [Ni(mnt)2]− ions are greater than the others in all crystals. The magnetic measurement data demonstrate that antiferromagnetic behavior was observed in 1 and can be fitted well through the 1D alternating linear chain model. Crystal 2 shows spin dimer magnetic behavior, and the magnetic susceptibilities of 3 and 4 show Curie–Weiss-type paramagnetic character in the whole temperature regions. This study showed that halogen substitution on the cations has significant effects on the arrangement and magnetic behavior of [Ni(mnt)2]−. [ABSTRACT FROM AUTHOR]

Two novel complexes, {[Cd 3 (L) 2 (H 2 O) 2 ]·(H 2 O) 4 } n (1) and {[Mn(HL)(H 2 O) 2 ]·(H 2 O)} n (2), which are synthesized by the reaction of 3-(2, 4-dicarboxyphenyl)-4-carboxypyridine ligand with cadmium and manganese metal ions under the solvothermal method. The complex 1 is a 3D framework based upon trinuclear [Cd 3 (μ 2 -COO) 4 (μ 1 -COO) 4 (N) 2 ] SBUs, and the complex 2 is a one-dimensional metal oxygen chain based upon binuclear [Mn 2 (μ 2 -COO) 2 (μ 1 -COO) 2 (N) 2 ] SBUs. The solid fluorescence analysis of complex 1 reveals that the emission peak of 451 nm when its excitation peak is 336 nm. The fluorescence detection experiments of complex 1 showed that Fe3+, Cr 2 O 7 2− and CrO 4 2− can effectively to be detected. Furthermore, their limits of detection are 1.47 × 10−3 M, 1.31 × 10−3 M and 1.25 × 10−3 M, respectively. It has good recovery properties as a potential multifunctional fluorescence sensor. Besides, the quenching mechanism of fluorescence sensing is also discussed. In addition, the magnetic studies of complex 2 show strong antiferromagnetic interactions between its neighboring Mn(II) ions. [Display omitted] • Two novel stable complexes were constructed based on particular trinuclear and binuclear metal clusters. • Complex 1 shows high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions with low detection limit. • Complex 2 possesses antiferromagnetic interaction between its Mn (II) ions. [ABSTRACT FROM AUTHOR]

A new metal-organic framework, {[Co1.5(μ2-OH)(L)(bipy)0.5] ·0.5DMF}n (1) (H2L = (4,4'-(hexafluoroisopropylidene)bis(benzoic acid) and bipy = 4,4'-bipyridine), has been prepared under solvothermal conditions using flexible dicarboxylate and rigid N-donor co-ligands in the presence of Co(II) ion as the building blocks. The x-ray single-crystal diffraction analysis indicates that 1 possesses a three-dimensional (3D) layer-pillar structure with one-dimensional (1D) metal-carboxylate chain. The Co(II) ions are bridged by L2- to generate a two-dimensional (2D) sheet, which is further pillared by bipy into a 3D framework with {44.62}{45.65}2 topology. In addition, the variable-temperature magnetic susceptibility measurement indicates there exists an anti-ferromagnetic behavior between in the Co(II) ions of 1. [ABSTRACT FROM AUTHOR]

Abstract: This work presents a systematic investigation on coordination chemistry of a novel pyridine-2,6-dicarboxylic acid N-oxide (pydco), and also reveals the significant function of supramolecular interactions in dominating the resultant crystalline nets. Assemblies of pydco with transition-metal ions under similar conditions yield a series of polymers in the absence/presence of the organonitrogen ligands {[Cu(pydco)(L)0.5(H2O)]·2H2O} n (L=bipy (1), bpa (2) and bpe (3)), {[M(pydco)(bpp)(H2O)]·2H2O} n (M=Cu (4) and Ni (5)), [Ag2(pydco)] n (6) and [Ag2Cu(pydco)2] n (7) (bipy=4,4′-bipyridine, bpa=1,2-bis(4-pyridyl)ethane, bpe=1,2-bis(4-pyridyl)ethene, bpp=1,3–bis(4-pyridyl)propane). 1–5 feature different structural characteristics, although they exhibit analogous chain networks. Remarkably, extended architectures are further constructed with the aid of weak interactions. Reaction of pydco with AgAc yields a 2-D polymer 6, which was reported in our recent Communication. A mixed-metal coordination polymer 7 was obtained by the self-assembly of AgAc, Cu(Ac)2 ·H2O and pydco. In 7, two left- and right-hand helical chains are constructed by carboxylic groups of pydco and Cu centers, which are further connected by [AgCO2]2 cores into a 2-D network. Structural evolution under the co-ligand intervention in this series of compounds, as well as the general coordination rule of pydco, has been further discussed. Furthermore, variable temperature magnetic properties of 1, 3 and 7 are also studied. The magnetic measurements of 1 and 3 reveal the existence of weak antiferromagnetic interactions with J 1 =−4.59cm−1 and J 2 =−4.63cm−1, respectively. Whereas 7 displays weak ferromagnetic interactions with J 3 =1.81cm−1. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]

Four copper(II) supramolecular complexes, {[Cu(Hpb)(mal)]·H 2 O} n (1), (Hpb  =  2-(2-pyridyl)-benzimidazole, mal  =  maleate), [Cu 4 (pb) 4 (cro) 4 (MeOH) 2 ]·2MeOH (2) (cro  =  crotonate), [Cu 2 (pb)(Hpb)(mac) 3 (MeOH)] (3) (mac  =  α-methacrylate) and [Cu(Hpb)(acr) 2 (H 2 O)] (4) (acr  =  acrylate), based on carboxylate copper(II)-aromatic ligand systems which are assembled by combination of metal coordination, hydrogen-bond and π–π interactions, have been rationally designed and synthesized. Complex 1 forms a 3D supramolecular network with open channels by extending 2D undulating sheets constructed from 1D helical chains. Complex 2 generates a 2D grid-like sheet via unusual finite-chain tetranuclear molecules, with four copper atoms arranged in a line; the unit does not extend further due to the capping effect of the terminal methanol. Complexes 3 and 4 present a 1D sinusoidal structure and a 3D columnar network with 1D ladder-shaped double chains, respectively. Interestingly, coligand Hpb, deprotonated or/and neutral in different supramolecular complexes, provides hydrogen bonding and π–π stacking interactions. In complexes 2, 3 and 4, carboxylate anions show various bridging modes, which are reflected in their magnetic properties. Weak ferromagnetic coupling (syn-anti µ-OCO) exists in 1, antiferromagnetic (syn-syn µ-OCO) and weak ferromagnetic coupling (µ-O of the  -COO group) in 2 and antiferromagnetic coupling (syn-syn µ-OCO) in 3. [ABSTRACT FROM AUTHOR]

• Two novel 2D MOFs based on diverse metal-oxygen chains with high open metal sites. • Zn-MOF possesses good selectivity and sensitivity to detect Fe3+ and Cr 2 O 7 2− ions with low detection limit. • The variable-temperature susceptibility of Mn-MOF indicates antiferromagnetic interaction between the Mn(II) ions. In this paper, two novel two-dimensional MOFs were synthesized by solvothermal reaction of 2,4-di(2′,5′-dicarboxylphenyl)benzoic acid ligand and Zn(Ⅱ) and Mn(Ⅱ) metal ions: {[Zn 2 (HL)(H 2 O)(DMF) 2 ]·(H 2 O)·(DMF)} n (1), {[Mn 2 (HL)(H 2 O)(DMF) 2 ]·(H 2 O)·(DMF)} n (2). Complexes 1 and 2 are unique two-dimensional skeletons with particular metal-oxygen chains in their structures. The solid-state luminescence spectrum of complex 1 shows that its maximum emission peak is 448 nm. Further fluorescence studies of complex 1 show that it can efficiently detect Fe3+ and Cr 2 O 7 2− in aqueous solution with a detection limit of 4.1 × 10−4 M and 2.7 × 10−4 M respectively, and has good recycling performance, so it is a potential bifunctional fluorescent probe material. The mechanism of fluorescence sensing quenching was also investigated in detail. Furthermore, magnetic studies have shown that there is an antiferromagnetic interaction between Mn(II) ions of complex 2. [Display omitted] [ABSTRACT FROM AUTHOR]

Herein, two new water-stable magnetic frameworks, [Cu1.5(L)(H2O)]·2H2O (1) and [Co4(L)2(CH3CN)(OH)2(H2O)4]·3H2O (2) (H3L = 5-((4-carboxypyridin-2-yl)oxy) isophthalic acid), were synthesized by a solvothermal method in similar reaction systems and characterized by infrared spectroscopy, powder X-ray diffraction and thermogravimetric measurements. Due to their different metal ions, 1 shows a trinodal (4,4,4)-connected three-dimensional (3D) framework that possesses 1D channels based on [Cu2(COO)4] paddle-wheel secondary building units (SBUs), whereas 2 is a 2D layered network based on tetranuclear [Co4(COO)6(μ3-OH)2] SBUs and reveals a (3,6)-connected kgd topological structure. The gas adsorption explorations demonstrated that 1 exhibited commendable selectivity for CO2 over CH4. Moreover, both 1 and 2 showed different degrees of antiferromagnetic exchange action. [ABSTRACT FROM AUTHOR]

By using a new 4,6‐bis(imidazol‐1‐yl) isophthalic acid ligand (H2bimip) with imidazolyl and carboxyl bifunctional groups, three new MOFs, [Co(bimip)(H2O)0.5]⋅0.5 H2O (1), [Zn(bimip)] (2), and [Mn(bimip)(H2O)2]⋅H2O (3), have been solvothermally synthesized in different solvent systems. H2bimip displays three different coordinated modes through the imidazolyl and carboxyl groups, and different cis–cis and trans–cis configurations, which result in distinct 3D topological frameworks: a (4,8)‐connected scu net for 1; a twofold interpenetrated (4,4)‐connected pts net for 2; and a four‐connected sra net for 3. Compounds 1 and 3 show antiferromagnetic properties, and 2 emits strong solid‐state blue luminescence. Compound 1 shows good chemical stability in acidic and basic environments and in boiling water. Additionally, the polar channels in 1, which are decorated by uncoordinated carboxylate O atoms and imidazolyl fragments, allow it to adsorb CO2 molecules selectively over CH4, and the CO2 binding sites in the framework were distinguished by molecular simulations. [ABSTRACT FROM AUTHOR]

A new porous metal-organic framework, namely [Co 3 (L)(OH) 2 (H 2 O) 4 ]·NMP·3H 2 O (1), has been yielded by using Co(II) and rigid V-shaped 2,6-di(2′,5′-dicarboxylphenyl)pyridine (H 4 L). The structure analysis revealed that MOF 1 is a three-dimensional (3D) porous framework with 1D [Co 3 (OH) 2 ] n ferromagnetic chains. The gas sorption measurements and the IAST analysis indicated MOF 1 has a relatively high selectivity for C 2 H 6 and CO 2 over CH 4. The magnetic properties indicated that MOF 1 has the ferrimagnetic and slow magnetic relaxation behavior, giving an interesting single-chain magnet behavior with an effective energy barrier of 15.82 K. A new 3D porous MOF 1 has been successfully synthesized. Gas sorption tests showed that MOF 1 has a relatively high adsorption capacity and selectivity for C 2 H 6 and CO 2 over CH 4. And also, MOF 1 displays the ferrimagnetic and slow magnetic relaxation behavior, giving an interesting single-chain magnet with an effective energy barrier of 15.82 K. Image 1 • The rigid V-shaped nitrogen heterocyclic carboxylic acid ligand 2,6-di(2′,5′-dicarboxylphenyl)pyridine(H 4 L) and Co(II) ions was selected as the building units to build porous crystalline MOF. • Structure analysis revealed that MOF 1 is a three-dimensional (3D) porous framework with 1D [Co 3 (OH) 2 ] n ferromagnetic chains. • Gas sorption measurements and the IAST analysis showed that MOF 1 has the higher adsorption selectivity for C 2 H 6 and CO 2 over CH 4. • Magnetic properties indicated that MOF 1 has the ferrimagnetic and slow magnetic relaxation behavior. [ABSTRACT FROM AUTHOR]

Five new 3D MOFs: {[Zn3(HL)2H2O]·4H2O}n (1), {[Ba2L5H2O]·2H2O}n (2), {[Ba4(L)2·5H2O]·2H2O}n (3), {[Cd3(HL)2·Cl2·2H2O]·2H2O}n (4) and {[Cu2(L)2·2H2O]·4H2O}n (5), were constructed based on 1-(3,5-dicarboxylatobenzyl)-3,5-pyrazole dicarboxylic acid. Structural analysis shows that 1–5 have 3D frameworks, among which 1(Zn) exhibits high luminescence sensing for Fe3+ ions, excellent framework stability and reusability. The sensing mechanism of 1(Zn) is briefly discussed. In addition, 5(Cu) displays antiferromagnetic exchange phenomena. [ABSTRACT FROM AUTHOR]

To better understand the factors determining the multi-step relaxation processes in polynuclear lanthanide single molecule magnets (SMMs), two Dy(iii)4 SMMs showing two-step relaxation processes were elaborately designed and investigated for their structure-dependent magnetic properties. Through targetedly fine-tuning the auxiliary ligand (from the anion of 1-phenylbutane-1,3-dione to 2-acetylcyclopentanone) on specific Dy(iii) sites while retaining the same type of coordination atoms, one of the two relaxation processes shifted to higher temperature with an increase of energy barrier, which permits the unambiguous assignment of the relaxation processes to specific metal sites. Therefore, the present {Dy4} systems provide a good example to probe the factors determining the relaxation dynamics, and point to a simple way to optimize the magnetic performance of polynuclear dysprosium SMMs. [ABSTRACT FROM AUTHOR]

A new ligand, rac-(R,S)-3,9-bis(pyridin-3-yl)-2,4,8,10-tetraoxaspiro[5.5]undecane ((R,S)-bptu), is synthesized, and five novel complexes, namely, {[Cu[(R,S)-bptu]Cl2]·0.5NMP}n (1), {[Zn[(R,S)-bptu]Cl2]·CH3CN}n (2), {Cd2[(R,S)-bptu]2Cl4(NMP)2}n (3), {[Cd[(R,S)-bptu]2Cl2]·2CH3CN}n (4), and {Cd3[(R,S)-bptu]2Cl6(DMF)2}n (5), (NMP = N-methyl-2-pyrrolidone, DMF = N,N-dimethylformamide), are obtained via a layered diffusional reaction. (R,S)-bptu and complexes 1–5 are characterized by single-crystal X-ray diffraction, element analyses, powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA). Complexes 1–3 show three different 1D structures: 1 is a mesomeric looped chain, 2 is a racemic helix compound, and 3 is a mesomeric zigzag chain, while 4 and 5 are two different mesomeric 2D structures, of which 4 is a 2D wave-like layer and 5 is a 2D cellular layer. Structural diversity indicates that the coordination preferences (cis- and trans-configurations) of (R,S)-bptu play a leading role in the self-assembly of complexes: cis-bptu tends to form one-dimensional structures 1–3, while trans-bptu is easier to construct higher dimensional structures 4–5. Secondly, the different transition metal atom M(ii) adopts diverse geometry in 1–5: Cu(ii) adopts square pyramidal geometry in 1, Zn(ii) employs a tetrahedron configuration in 2, and especially in 3–5, Cd(ii) displays a trigonal bipyramidal configuration, cis-cis–trans, cis and trans octahedral configuration. Finally, the different solvent system, the coordinated/free solvent, and the secondary building units (SBUs) affect the diversification of the structure. A variable temperature magnetic susceptibility investigation manifests that antiferromagnetic interactions exist between the neighbouring metal ions in 1. Furthermore, the luminescence properties of 2–5 are investigated in the solid state at room temperature, and 4 shows highly selective and sensitive sensing for Fe3+ ions. [ABSTRACT FROM AUTHOR]

Abstract In order to explore the metal ions-controlled syntheses of coordination polymers (CPs), the temperature and solvent ratio were fixed in the reaction processes. By selecting a series of s- and d-block metal ions, five new CPs, [ZnL 0.5 (H 2 O) 2 ] n (1), [CoL 0.5 (H 2 O) 2 ] n (2), [Mn(H 2 L)(H 2 O) 2 ] n (3), [Ca(H 2 L)(H 2 O) 2 ] n (4) and [Ba(H 2 L)(H 2 O) 2 ] n (5), have been synthesized by employing a less-investigated oxalamide N,N′ -bis(4-phthalic acid) (H 4 L) ligand. H 4 L shows very versatile coordination modes and leads to various frameworks, including isomorphous 2D grid-like layer based on M 2 O 2 cores for 1 and 2 , isomorphous 4-connected 3D PtS frameworks based on 1D [M(CO 2) 2 ] n chains for 3 and 4 , and a 2D wave - like layer based on [BaO 3 ] n chains for 5. 2 and 3 reveal the antiferromagnetic and ferromagnetic properties, respectively, while 1 , 4 and 5 possesses strong solid state luminescence. Graphical abstract Five new CPs with magnetic properties and luminescence have been constructed based on s- and d-block metals, and the oxalamide N,N′ -bis(4-phthalic acid) ligand displays versatile coordination modes and various architectures. fx1 Highlights • Five CPs were constructed by an oxalamide N,N′ -bis(4-phthalic acid) ligand. • The versatile coordinated modes of ligands lead to various architectures of CPs. • Antiferromagnetic and ferromagnetic properties as well as luminescence were found. [ABSTRACT FROM AUTHOR]

The reactions of an unexploited N,N′‐5‐carboxyl‐1,3‐phenylenebis(ethyl oxamate) (HEt2L) ligand with different Mn2+ and Cd2+ salts under solvothermal conditions afforded four three‐dimensional (3D) coordination polymers (CPs): [Mn1.5L(H2O)2]⋅H2O (1) [Mn2L(C2O4)0.5(NMP)(H2O)] ⋅ NMP (2), [Cd1.5L(H2O)2.5] ⋅ H2O (3) and [Cd2L(C2O4)0.5(H2O)3] ⋅ H2O (4) (NMP=N‐methyl pyrrolidone). L, generated by the in‐situ hydrolysis of HEt2L, displays four kinds of coordinating modes through oxamate and carboxylate groups as well as different syn‐syn and syn‐trans configurations. The resulting novel (3,4,5)‐, (3,4,6)‐, (4,5)‐ and (4,4,4,5)‐connected topologies for 1–4 were formed. Among them, 1 has interesting 1D metal‐oxamate zigzag chains, 2 contains 1D channels with a free void of 52.5 %, 3 consists of an unprecedented Cd‐oxamate layer, 4 has a novel Cd‐oxamate‐oxalate chain. The antiferromagnetic interactions of 1 and 2 were observed, meanwhile 3 and 4 exhibit solid‐state luminescence with the maximum emission bands at 483 and 479 nm, respectively, under an excitation of 332 nm. Structural Diversity: Four novel coordination polymers (CP) were constructed by Mn2+ and Cd2+ ions with N,N′‐5‐carboxyl‐1,3‐phenylenebis (oxamic acid), showing framework diversity caused by various ligand coordinating modes (See figure). In addition, antiferromagnetic interactions and exhibit solid‐state luminescence properties were investigated. [ABSTRACT FROM AUTHOR]

Using a triazole carboxylic ligand (H2L = 4-(1H-1,2,4-triazol-1-yl) isophthalic acid), four water-stable lanthanide metal-organic frameworks (Ln(III)-MOFs) (1-Ln, Ln(III) = Tb, Eu, Dy, and Sm), [Ln(L)(HL)(H2O)2], where the deprotonated H2L ligands have two different coordination modes: L2− and HL− [(a): η2μ2χ2, η2μ1χ2; (b): η2μ1χ2], have been synthesized by solvothermal reaction and characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analyses show that Ln(III)-MOFs are isostructural with 2D-layered structures with uncoordinated carboxylic and triazole groups. The luminescent properties of 1-Tb in aqueous solution containing different cationic solutions and small organic solvents have been explored under ultraviolet irradiation at room temperature. The high quenching constant KSV values and low detection limits indicate that 1-Tb exhibits extremely high detection sensitivity and selectivity toward Fe3+ ions and nitrobenzene; 1-Tb can keep its original network and be reused after the sensing experiments, which provide us with an optical material for detecting Fe3+ ions and nitrobenzene. Magnetic studies show that antiferromagnetic exchange interactions exist between Dy(III) ions in 1-Dy. [ABSTRACT FROM AUTHOR]

Three metal-organic frameworks (MOFs), [Cd(Hpzbpdc)(H2O)].H2O (1), [Mn2(Hpzbpdc)2(dmf)2] (2), and [H2N(CH3)2]0.5[Eu(Hpzbpdc)1.5(HCOO)0.5(dmf)0.5].DMF.0.5H2O (3) (H3pzbpdc=4'-(2H-pyrazol-3-yl)biphenyl-3,5-dicarboxylic acid), have been solvothermally synthesized from one pyrazoyl-carboxyl bifunctional ligand and characterized by single-crystal structures. The H3pzbpdc ligand in 1-3 displays various coordination modes through the pyrazoyl and carboxyl groups. Both 1 and 3 contain dinuclear cluster building units and reveal a four-connected gismondine (gis) zeolite 3D framework and a 2D grid layer structure, respectively. Compound 1 shows blue luminescence, compound 3 reveals red luminescence that arises from efficient energy transfer from the organic ligand to the europium(III) ion, and compound 2 reveals an uncommon (3,8)-connected tfz-d; UO3 net with a rare Mn6(COO)6 cluster and shows antiferromagnetic interactions between the manganese( II) ions. [ABSTRACT FROM AUTHOR]

By using an asymmetrical rigid pentacarboxylic acid ligand, 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid (H5L), four new three-dimensional (3D) metal–organic frameworks (MOFs), namely {[Cu2(HL)(H2O)2]·2DMF·2H2O}n (1), {[Co2(L)(DMA)]·H2N(Me)2}n (2), {[Co2(L)(H2O)]·H2N(Me)2}n (3), {[Mn2(L)(DMF)(H2O)]·H2N(Me)2}n (4), were solvothermally synthesized. H5L in 1–4 shows different coordination modes and can easily form various metal clusters (secondary building units, SBUs) in the final structures. 1 is a 3D porous framework with a (4,4)-connected pts topology based on the [Cu2(COO)4] paddlewheel SBU, wherein six SBUs are connected by twelve HL4− to get an unprecedented Cu12 hendecahedron nanocage. 2–4 possess similar dinuclear [M2(COO)5] SBUs (M = Co, Mn), which are further extended by L5− to give rise to 3D frameworks with the uncommon (5,5)-connected nia-5,5-P21/c and bnn topologies. In addition, the desolvated framework of 1 contains polar channels decorated with uncoordinated carboxylate groups, leading to selective adsorption for CO2 over CH4 at 195, 273 and 298 K. Moreover, the magnetic properties of 1–4 show that there exist antiferromagnetic interactions between metal ions. [ABSTRACT FROM AUTHOR]

By treating a semirigid 5-oxyacetate isophthalic acid (H3OAIP) ligand with MnSO4/CoSO4/CdSO4 under solvothermal conditions, three isostructural cluster organic frameworks, [M2(OH)(OAIP)(DMA)] ⋅H2O (M=Mn2+ ( 1), Co2+ ( 2), Cd2+ ( 3); DMA= N,N′-dimethylacetamide) were constructed. The three complexes contain novel eight-connected tetranuclear M4(OH)2(COO)6(OCH2COO)2 clusters with the unique hexagonal bipyramidal configuration, which are extended by four-connected OAIP linkers to form an uncommon (4,8)-connected alb-4,8-Cmce topology based on (3,6)-connected kgd sublayers. Both 1 and 2 showed significant antiferromagnetic interactions between the intracluster metal ions, whereas 3 revealed strong blue photoluminescence. [ABSTRACT FROM AUTHOR]

Two new Co(II) metal-organic frameworks, namely [Co 2 (bpm)(H 2 O) 3 (L)] n ( 1 ) and {[Co(bpe)(H 2 O)(H 2 L)]·(bpe) 0.5 ·(H 2 O)} n ( 2 ), (H 4 L=1,1′:2′,1″-terphenyl-3,3″,4′,5′-tetracarboxylic acid, bpm=bis(4-pyridyl)amine, bpe=1,2-bis(4-pyridyl)ethene), have been obtained under hydrothermal conditions. Both complexes 1 and 2 have been characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Complexes 1 and 2 consist of 1D Co(II) chains bridging by carboxylate groups in syn-anti fashion. 1 shows a novel 3D tri-nodal (4,6,10)-connected net with a (3.4 3 .5 2 ) 2 (3 2 .4 14 .5 12 .6 12 .7 4 .8)(3 2 .4 2 .5 5 .6 4 .7 2 ) topology. While 2 exhibits a 2D sql layer. Magnetic susceptibility measurements indicate that both 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions in 300–8 K for 1 and 300–16 K for 2 , respectively, and then 2 also displays ferromagnetic coupling at lower temperatures. [ABSTRACT FROM AUTHOR]

A series of new 1D isomorphic lanthanide metal-organic frameworks (Ln-MOFs), {[Ln(L)(H 2 O) 5 ]·2H 2 O} n (1-Ln , Ln ​= ​Eu, Tb, Dy and Eu x Tb 1-x), were synthesized via a rigid bifunctional N,O-containing 2-(1 H -tetrazol-5-yl)terephthalic acid (H 2 L) and Ln(III) ions as raw materials. It is worth noting that different ratios of Eu(III) and Tb(III) can be combined into the same Ln-MOFs to generate a series of new differently doped 1-Eu x Tb 1-x MOFs. Under the same excitation wavelength, the double emission peaks of Eu(III) and Tb(III) are produced, and the emission color gradually changes between yellow-green, yellow, orange, and red. The sensing studies have shown that 1-Tb is an excellent reusable luminescence probe, suitable for simultaneous detection of dimetridazole (DMZ), metronidazole (MDZ) and tetracyclinehydrate (TET) in the aqueous solutions. Furthermore, magnetic measurements show that 1-Dy has slow magnetic relaxation properties. A series of new 1D isomorphic lanthanide metal-organic frameworks (Ln-MOFs), {[Ln(L)(H 2 O) 5 ]·2H 2 O} n (1-Ln , Ln ​= ​Eu, Tb, Dy and Eu x Tb 1-x), had been synthesized, and the 1-Eu x Tb 1−x doped MOFs achieve tunable emission from yellow-green to yellow to red. Besides, 1-Tb can be used to detect dimetridazole (DMZ), metronidazole (MDZ), and tetracycline (TET) in water and serum sensitively and selectively through fluorescence quenching, and 1-Dy has a slow magnetic relaxation performance. [Display omitted] • Series of isostructural Ln-MOFs had been synthesized by a rigid ligand. • A series of doped 1-Eu x Tb 1−x MOFs were obtained to achieve tunable emission. • 1-Tb has the high selectivity and sensitivity to detect DMZ, MDZ and TET. • 1-Dy has the slow magnetic relaxation properties. [ABSTRACT FROM AUTHOR]

Based on the N-donor auxiliary ligand effect, two new Ni(II) coordination polymers [Ni 2 (HL) 2 (bpe) 2 ] ( 1 ) and [Ni(HL)(bipy)(H 2 O) 2 ] ( 2 ) [H 3 L = 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 6 6 , while 2 , containing bipy ligands, exhibits a two-dimensional (2D) sql layer structure with a 4-connected (4 4 ·6 2 ) topology. Moreover, the magnetic properties for 1 and 2 were also measured and compared on account of their different structures. [ABSTRACT FROM AUTHOR]

The 1D complex [(CuL0.5H2O) ⋅H2O] n ( 1) (H4L=2,2′-bipyridine-3,3′,6,6′-tetracarboxylic acid) undergoes an irreversible thermally triggered single-crystal-to-single-crystal (SCSC) transformation to produce the 3D anhydrous complex [CuL0.5] n ( 2). This SCSC structural transformation was confirmed by single-crystal X-ray diffraction analysis, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) patterns, variable-temperature powder X-ray diffraction (VT-PXRD) patterns, and IR spectroscopy. Structural analyses reveal that in complex 2, though the initial 1D chain is still retained as in complex 1, accompanied with the Cu-bound H2O removed and new O(carboxyl)Cu bond forming, the coordination geometries around the CuII ions vary from a distorted trigonal bipyramid to a distorted square pyramid. With the drastic structural transition, significant property changes are observed. Magnetic analyses show prominent changes from antiferromagnetism to weak ferromagnetism due to the new formed Cu1-O-C-O-Cu4 bridge. The catalytic results demonstrate that, even though both solid-state materials present high catalytic activity for the synthesis of 2-imidazolines derivatives and can be reused, the activation temperature of complex 1 is higher than that of complex 2. In addition, a possible pathway for the SCSC structural transformations is proposed. [ABSTRACT FROM AUTHOR]

Employing an uninvestigated eight N-donor bitriazole ligand, 5'-(pyrazin-2-yl)-2H,4'H-3,3'-bi(1,2,4-triazole) (H2pzbtz), five complexes, {[Zn2(pzbtz)(SO4)(H2O)2]·2H2O}n (1), {[Cd(pzbtz)]·3H2O}n (2), [Zn3 (Hpzbtz)2(SO4)2(H2O) 6] (3), [Co(Hpzbtz)2(H2O)2] (4) and {[Co2(pzbtz)2(H2O)2]·4H2O}n (5), have been solvothermally synthesised by altering the reaction solvents and temperatures. Complex 1 shows a three dimensional (3D) framework with a very rare (3,5)-connected fsc-3,5-Cmce-2 topology. Complex 2 exhibits a (4,4)-connected 3D pts framework with 1D channels. Complexes 3 and 4 are discrete trinuclear and mononuclear molecules, respectively. Complex 5 presents a chiral 3D framework based on a novel trinuclear Co3 (tr) 4 cluster and features an unusual six-connected lcy topology. In the five complexes, H2pzbtz show a very variety of geometrical configurations and coordination modes. Due to the planarity of H2pzbtz, complexes 1-3 display strong photoluminescence; in particular, 1 features highly selective luminescent sensing for the Cu2+ ion and nitrobenzene molecule. In addition, 2 shows highly selective adsorption for CO2 over CH4, and 5 exhibits antiferromagnetic exchange interactions among the Co2+ ions. [ABSTRACT FROM AUTHOR]

An unusual three-dimensional Co(II)-based pillar-layered coordination polymer [Co2(L)(bipy)(OH)(H2O)]n·nCH3CN (1, H3L=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 Schläfli symbol of (43)2(46·618·84), 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. [ABSTRACT FROM AUTHOR]

Abstract: A new three-dimensional porous framework [Co2(bpdc)2(H2bpz)]∙2(DMF)·5(H2O) (1) (H2bpdc=4,4′-biphenyldicarboxylic acid, H2bpz=3,3′,5,5′-tetramethyl-4,4′-bipyrazole) has been solvothermally synthesized by employing mixed H2bpdc and H2bpz ligands. 1 is a pillared-layer framework based on a binuclear paddle-wheel Co2(O2C-R)4 cluster, and exhibits a 2-fold interpenetrated 6-connected pcu topology. H2bpz bridges Co2(O2C-R)4 clusters with an angular coordination configuration to form interesting left- and right-handed helical chains. 1 possesses a two-dimensional porous system decorated by uncoordinated pyrazole –NH groups of H2bpz, leading to high adsorption selectivities for CO2 over N2 and H2. In addition, the strong antiferromagnetic interactions between the Co2+ ions in cluster were observed. [Copyright &y& Elsevier]

Abstract: The self-assembly of a V-shaped ligand 3,3′,4,4′-diphenylsulfonetetracarboxylate (dstc) and metal salts in the presence of a series of N-donor ligands yielded four new complexes, namely, [Cu4(H2dstc)4(phen)4]·12H2O (1), {[Cu2(dstc)(bpe)(H2O)2]·4H2O} n (2), [Cu3(dstc)(bipy)(μ2-OH)2(H2O)2] n (3), {[Cd5(dstc)2(bipy)2(μ3-OH)2(H2O)4]·4H2O} n (4) (phen=1,10-phenanthroline; bpe=1,2-bis(4-pyridyl)ethene; bipy=4,4′-bipyridine). All the complexes were structurally determined by single-crystal X-ray diffraction and characterized by elemental analyses, IR spectra, X-ray powder diffraction and TG analyses. Complex 1 is a discrete tetranuclear unit, which further assembles into a 3D supramolecular framework by intermolecular hydrogen bonding interactions. Complex 2 is composed of 2D 44 grid-like layers based on dinuclear copper units. Complex 3 features a rare 3D (6,8)-connected topological net consisting of trimetallic clusters. 12-connected pentanuclear cadmium clusters are observed in complex 4 and the resulting structure shows an uncommon (4,12)-connected topology. The structural differences among 1–4 demonstrate that the nature of the N-donor assistant ligands and metal ions can play critical roles in the formation and structures of the resulting complexes. Magnetic studies showed antiferromagnetic interactions for 1 and 3. In addition, the luminescent property of 4 was also studied. [ABSTRACT FROM AUTHOR]

Seven new complexes based on the bifunctional ligand were synthesized under hydro(solvo)thermal conditions. 1 – 7 adopts different coordination modes and generates diverse 1D or 2D structures. • The L2−/HL− ligand in 1 – 7 adopts different coordination modes and generates diverse structures. • Compound 1 shows highly selective and sensitive response to Fe3+. • Compound 1 shows highly selective sensitivity for Cr2O 7 2− and MnO 4 2−. Seven new complexes based on 4-(3-carboxyl-1,2,4-1H-triazol-1-yl)benzoic acid (H 2 L), namely [Zn(L)(H 2 O) 2 ] n (1), [Cd(L)(H 2 O) 2 ] n (2), [Pb(HL) 2 ] n (3), [Pb(L)(H 2 O)] n (4), [Cu(L)(H 2 O) 2 ] n (5), [Co(L)(H 2 O) 2 ] n (6) and [Mn(L)(H 2 O) 2 ] n (7), were synthesized by employing different center metal ions and a imidazol-carboxyl bifunctional ligand (H 2 L) under hydro(solvo)thermal conditions. The L2−/HL− ligand in 1 – 7 adopts different coordination modes and generates diverse 1D or 2D structures. The luminescent and magnetic properties of seven complexes were investigated in detail. Moreover, complex 1 shows high selectivity for Fe3+, Cr 2 O 7 2− and MnO 4 − ions, indicating that 1 can be an excellent candidate for luminescence sensing. In addition, complexes 5 , 6 and 7 demonstrate antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]