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Eight novel coordination polymers, {[LnZn(2,3-pydc) 2 (ox) 0.5 (H 2 O) 3 ]·3H 2 O} n (Ln = Pr 1 , Nd 2 , Ho 3 , Er 4 , Yb 5 , Sm 6 , Eu 7 , Tb 8 ) (2,3-H 2 pydc = pyridine-2,3-dicarboxylic acid, H 2 ox = oxalic acid) are synthesized by the hydrothermal method and their structures are determined by single-crystal X-ray diffraction. They are isomorphous and crystallized in the triclinic system, with space group P 1 ¯ . In crystals, Ln(III) and Zn(II) ions are linked into 2D layers by 2,3-pydc 2− ligands adopting two coordination modes, and neighboring layers are bridged into 3D network structure through oxalate ligands in bridging tetradentate coordination mode. The IR, UV–Vis–NIR absorption spectra and emission spectra in the visible and near-infrared (NIR) region of polymers are determined and analyzed. All of polymers exhibit characteristic emission bands of corresponding Ln(III) ions, which should be attributed to sensitization from the d-block (Zn–ligand moiety) and ligands after introducing Zn(II) ion into the system of Ln(III) complexes. [ABSTRACT FROM AUTHOR]

The syntheses, structures,and characterization of three seriesof one-dimensional (1D) and three-dimensional (3D) 3d–4f cluster-basedpolymers with AA (HGly or HAla) and formate as mixed ligands are described.Under the pH values of 6.0 and 5.2, respectively, three 1D undulatingchains [Ln = Gd, (1); Tb, (2); and Dy(3)] and two 3D frameworks [Ln = Gd, (4) and Tb,(5)] with a 3-connected pcu-hnetworkwere obtained. Both of them use Gly-based heptanuclear trigonal prism[LnCu6] clusters and mononuclear Ln3+as nodeslinked by syn–anti formate ligands. Moreover, three 3D polymers[Ln = Gd, (6); Tb, (7); and Dy (8)] with a 6-connected pcunetwork were built fromAla-based [Ln6Cu24] clusters and formate bridges.The formate ligand played an important role not only for the constructionof the cluster units but also for their further linkage to extendedarrays. Magnetic analyses indicate the three Gd3+-containingcompounds bear an interesting magnetocaloric effect, and the −ΔSm(T) values are 5.8, 6.0, and 18.8 J kg1–K–1(ΔH= 5 T) for 1, 4, and 6, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Three Ag(I) coordination complexes, [Ag(pyzca)]n (1) (Hpyzca=pyrazine-2-carboxylic acid), Ag[(HNA)(NA)(H2O)4] (2) (HNA=nicotinic acid) and [Ag1Ag2-(2,3-pydc)]n (3) (H2pydc=pyridine-2, 3-dicarboxylic acid) have been synthesized by the hydrothermal method. Their structures are determined by single-crystal X–ray diffractometer. Complex 1 possesses the 3D infinite structure. Complex 2 is a mononuclear coordination complex and exhibits one 3D infinite network by a large number of hydrogen bonds. In complex 3, two crystallographic independent Ag(I) ions exist, i.e., Ag1 is three-coordinate and Ag2 is two-coordinate, forming the 2D layer structure. At room temperature in the solid state, the IR, FP and UV–Vis spectra of all complexes were measured and investigated in detail. The emission and absorption spectra of the three complexes and their corresponding ligands are compared and analyzed. [Copyright &y& Elsevier]

Abstract: Using aromatic carboxylic acids as main ligands, four Ln(III) coordination polymers, [Er(CH3C6H4COO)2(Ac)(H2O)] n (1), [Yb(β-C10H7COO)2(Ac)(H2O)] n (2), [Nd(C9H7O2)3] n (3) and [Ho(C9H7O2)3] n (4) (CH3C6H4COO= p-toluylate, Ac=acetate, β-C10H7COO= β-naphthoyloxy, C9H7O2 =cinnamate), were synthesized by hydrothermal method and their structures were studied by single-crystal X-ray diffraction. Polymers 1 and 2 possess 2D layer structures, and polymers 3 and 4 possess 1D chain structures. At room temperature in the solid state, the IR, UV–Vis–NIR spectra and the emission spectra in the visible and near-infrared (NIR) regions of the four polymers were determined. In the NIR region, polymers 1–4 show characteristic emission bands of the corresponding Ln(III) ions which exhibit shift, splitting or broadness in comparison with their theoretical emission bands. This can be confirmed by their UV–Vis–NIR spectra and discussed emphatically. [Copyright &y& Elsevier]

Four new lanthanide(Ш) coordination polymers, [Ln( p-aminobenzoate)(DMF)(HCOO) (HO)] (Ln = Sm 1, Tb 2, Pr 3) and {[Pr(2,5-dcp)(CHCOO)(HO)]·1.5HO} ( 4) (DMF = N, N-dimethylformamide, 2,5-dcp = pyridine-2,5-dicarboxylate), have been synthesized by hydrothermal method. The structures are determined by the single-crystal X-ray diffraction. The four polymers all crystallize in the monoclinic space group P2/n. Polymers 1 and 2 are isostructural; both Sm ion of polymer 1 and Tb ion of polymer 2 are eight-coordinate. Although polymer 3 possesses the same asymmetric unit as polymers 1 and 2, the three are not isomorphous. The Pr ions in polymers 3 and 4 are nine-coordinate. In polymers 1, 2 and 3 the neighboring units are bridged by formyloxy and extend into infinite chains, which are connected by hydrogen bonds to form a hydrogen bond network. However, polymer 4 is bridged by pyridine-2,5-dicarboxylate and acetates to form an infinite 3D network. At room temperature, the IR, UV-Vis-NIR and emission spectra of the four polymers were measured and analyzed. The four polymers emit in the visible or NIR region. The luminescent properties are discussed. [ABSTRACT FROM AUTHOR]

C23H19FeN3O3S, monoclinic, P21/n (no. 14), a=13.1372(6) Å, b=9.6866(5) Å, c=15.9700(8) Å, β=92.499(2)°, V=2030.33(17) ų, Z=4, Rgt(F)=0.0294,wRref(F²)=0.0807, T=296(2)K [ABSTRACT FROM AUTHOR]

Abstract: Six novel heterometallic Zn–Ln coordination polymers {[ZnLnCl(pydc)2(H2O)6]·3H2O} n (Ln=Nd 1, Pr 2, Sm 3, Eu 4, Tb 5, Dy 6; pydc=pyridine-2,5-dicarboxylate) were synthesized by the hydrothermal method, and their structures were measured by the single-crystal X-ray diffraction. The IR and UV–Vis–NIR absorption spectra, and the luminescence spectra in the visible and near-infrared (NIR) regions of the six complexes were determined at room temperature. They possess the same crystal structure, and the Zn(II) and Ln(III) ions in each complex are bridged into 1D infinite chain by pyridine-2,5-dicarboxylates. Meanwhile, there are numerous hydrogen bonds which result in the 3D hydrogen bonding network in the crystal. In the visible and NIR regions, the emission spectra of the complexes show the characteristic bands of the corresponding Ln(III) ions, which are mainly attributed to the sensitization from the d-L-moiety to f-L-moiety after forming the Zn–Ln complexes. In this paper, we first report the Zn–Sm complex which can exhibit the emission bands of Sm(III) in the NIR region, and discuss the sensitization from the d-L-moiety to f-L-moiety on the basis of the different characteristics of levels for different Ln(III) ions. [Copyright &y& Elsevier]

Abstract: A novel diperoxovanadate complex NH4[OV(O2)2{2-(2′-pyridyl)-imidazole}]·4H2O was synthesized in aqueous solution under physiological conditions. The solution structure of the complex was characterized by multinuclear (1H, 13C, 14N, and 51V) as well as multi-dimensional (DOSY and C-H COSY) NMR techniques in the interaction system of NH4VO3/H2O2/2-(2′-pyridyl)-imidazole at room temperature. The crystal structure of the complex was determined at 173K by single-crystal X-ray diffraction method. It belongs to the monoclinic space group P21/c with a =13.048(4), b =6.984(2), c =17.814(5) Å, β =104.695(5), V =1570.3(8) Å3 and Z =4. The crystal is composed of ammonium ions, {2-(2′-pyridyl)-imidazole}oxodiperoxovanadate(V) ions, and water molecules, which are held together by ionic and hydrogen bond forces. The metal atom in the complex is seven-coordinated with a distorted pentagonal bipyramidal geometry. It is the first mononuclear diperoxovanadate complex with a N, N′-chelating biheteroaromatic ligand and its 51V chemical shift is at the highest field among the known mononuclear diperoxovanadate(V) complexes. [Copyright &y& Elsevier]

1, 4, 5, 8‐naphthalene diimide (NDI)‐based MOFs, due to their tunable structures and properties, have shown promising applications in photochromism, photocatalysis, electrocatalysis, photothermal therapy, etc. Herein, using an L‐alanine modified NDI ligand, i.e. N, N′‐bis(L‐alanine)naphthalenediimide (AlaNDI), a novel Cd‐NDI Cd (AlaNDI)(H2O)]·DMF·H2O (complex 1) was constructed under solvothermal conditions, which has an obvious different structure with the previously reported ones. Structural analysis shows that the packing structure of complex 1 consists of two adjacent Cd atoms sharing two AlaNDI ligands, forming a dimetallic building block [Cd2O8]. Each building block connects a total of four AlaNDI ligands, where two Cd atoms are bridged by two ligands. The building blocks are interconnected by ligands to form a two‐dimensional layered structure. Based on the features of the NDI skeleton, it was found that complex 1 possesses multiple stimulus responses involving sensitivity to light: a reversible photochromism property and good photocatalytic degradation activity against various dyes, especially against cationic dyes crystal violet (CV), methyl violet (MV), and Janus green B (JGB). In addition, the stimulus‐response mechanism was investigated by control experiments. It is revealed that the photocatalytic active species may be related to h+ and •OH. [ABSTRACT FROM AUTHOR]

Seven coordination polymers having the general formula {[Ln2(2,6-pydc)(ox)2⋅(H2O)4]⋅3H2O}n (Ln = Sm 1, Eu 2, Gd 3, Tb 4, Dy 5, Ho 6, Er 7; 2,6-pydc2− = 2,6-pyridinedicarboxylate, ox2− = oxalate) were synthesized by the hydrothermal method. Their IR, UV-Vis-NIR absorption spectra, and Vis-NIR emission spectra were investigated, and the luminescent properties of the polymers were studied in detail. Crystal structures were determined by means of a single-crystal X-ray diffractometer, and all of them proved to have three-dimensional frameworks. Except for polymers 3 and 7, the polymers displayed the characteristic emissions of Ln(III) ions due to the effective sensitization of ligands. At the same time, the 4f orbitals of Ln(III) ions were shifted by the effects of ligand field, which influenced emission spectra and absorption spectra of some of the polymers. [ABSTRACT FROM AUTHOR]

[Cd(C15H13N5)2Cl2], monoclinic, C2/c (no. 15), a = 15.6291(6) Å, b = 12.8859(4) Å, c = 14.7622(5) Å, β = 97.781(3)°, V = 2945.65(18) Å3, Z = 4, Rgt(F) = 0.0381, ωRref(F2) = 0.0738, T = 293(2) K. [ABSTRACT FROM AUTHOR]

A series of coordination polymers, {[LnZn(2,3-pydc)(1,3-bdc)(OH)(H 2 O) m ] · H 2 O} n , (Ln = Sm 1 , Eu 2 , Gd 3 , Tb 4 , Dy 5 , Er 6 , Yb 7 , Pr 8 , Nd 9 ), ( 1 – 7 , m = 1; 8 , 9 , m = 2), (2,3-H 2 pydc = pyridine-2,3-dicarboxylic acid, 1,3-H 2 bdc = isophthalic acid), are synthesized by the hydrothermal method and their crystal structures are determined by single-crystal X-ray diffraction. Structural analysis shows that coordination polymers 1 – 9 present two-dimensional layered structures and all of them are crystalized in triclinic system with space group P ī. Hereinto polymers 1 – 7 are isomorphous, while polymers 8 and 9 are also isomorphous and each of them includes one more coordinated water molecule than others. All coordination polymers are characterized by IR, UV–Vis–NIR and fluorescent spectra, and the luminescent properties are the research emphasis. In addition, except for polymer 3 , the other eight Zn-Ln polymers exhibit the characteristic luminescence of corresponding Ln(III) ions, which should be owing to the sensitization of the Zn-Ligand moiety. With the influence of the crystal field and the introduction of Zn(II) ion, the internal energy levels of the system are tuned, which is reflected by shift and split of the partial characteristic bands of Ln(III) ions in their UV–Vis–NIR absorption spectra and NIR emission spectra, and both can corroborate each other. [ABSTRACT FROM AUTHOR]

Six Zn-Ln coordination complexes, [Nd 2 Zn 2 (C 6 H 5 COO) 10 (Imh) 2 (H 2 O) 2 ] ( 1 ), [Pr 2 Zn 2 (C 6 H 5 COO) 10 (Imh) 2 (H 2 O) 2 ] ( 2 ), [ErZn 2 (C 6 H 5 COO) 7 (Imh) 2 ] ( 3) , [HoZn 2 (C 6 H 5 COO) 7 (Imh) 2 ] ( 4 ), [EuZn 2 (C 6 H 5 COO) 7 (Imh) 2 ] ( 5 ), [TbZn 2 (C 6 H 5 COO) 7 (Imh) 2 ] ( 6 ) (C 6 H 5 COOH=benzoic acid, Imh=imidazole) have been synthesized under hydrothermal conditions and their crystal structures have been characterized by single crystal X-ray diffraction. All complexes are crystallized in triclinic system, with space group P ī. Complexes 1 and 2 are isomorphous with tetranuclear molecular structure and complexes 3–6 are isomorphous and trinuclear molecular complexes. All complexes are characterized by IR, UV–Vis–NIR and luminescent spectra in the visible and near-infrared (NIR) regions at room temperature. The study of luminescent properties indicates that all complexes exhibit the characteristic emission bands of corresponding Ln(III) ions, which should be attributed to sensitization from d-block and ligands after introducing Zn(II) ion and ligands into the system of Ln(III) complexes. Moreover, the NIR emission bands of complexes 1–4 exhibit shift and split, which can be evidenced in their UV–Vis–NIR absorption spectra. [ABSTRACT FROM AUTHOR]

Fourteen Ni/Co-Ln heterometallic coordination polymers were successfully synthesized. All CPs are bridged into the 3D network structure by 2,3-pydc2- and ox2- and exhibit characteristic emission bands of the corresponding Ln(III) ion. [Display omitted] • A series of heterometallic NiII/CoII-LnIII coordination polymers have been synthesized by using pyridine-2,3-dicarboxylic acid as main ligand. • They exhibit characteristic luminescence of Ln(III) ions. • NIR emission bands of Ln(III) ions in some polymers present shift, split and broad under the double influence from the crystal field and Ni(II) or Co(II) ions. Fourteen isomorphic heterometallic coordination polymers (CPs) with general formulas of {[LnM(2,3-pydc) 2 (ox) 0.5 (H 2 O) 3 ]·3H 2 O} n (M = Ni, Ln = Pr 1 , Nd 2 , Sm 3 , Eu 4 , Gd 5 , Tb 6 , Dy 7 ; M = Co, Ln = Pr 8 , Nd 9 , Sm 10 , Eu 11 , Gd 12 , Tb 13 , Dy 14 ; 2,3-pydc2– = fully deprotonated pyridine-2,3-dicarboxylic acid, ox2– = fully deprotonated oxalic acid) have been synthesized by hydrothermal methods. All the CPs crystallize in triclinic P -1 space group and exhibit a 3D network formed by 2,3-pydc2– and ox2– bridging Ln(III) and Ni(II)/Co(II) ions. Meamwhile the room temperature photoluminescent properties have been explored. Except for CPs 5 and 12 , the other CPs exhibit characteristic luminescence of Ln(III) ions. [ABSTRACT FROM AUTHOR]

Abstract: A novel cobalt(II) complex [Co3(oba)3(phen)2]n(H2oba=4,4′-oxybis benzoic acid, phen=1,10-phenanthroline) has been synthesized by hydrothermal method and characterized by single crystal X-ray diffraction, IR, UV–vis, thermal stability and Surface Photovoltage Spectroscopy (SPS). Structural analysis indicated that the complex is a 3D structure with the trinuclear building unit of [Co3(oba)3(phen)2] bridged by the oba ligands. The SPS of complex indicates that there are positive response bands in the range of 300–600nm showing photo-electric conversion properties. There are good relationships between SPS and UV–vis spectra. [Copyright &y& Elsevier]

Abstract: Four Fe(II/III) supramolecules, {[Fe(Hpdc)2(H2O)2]·2H2O} (1), [Fe(HImbc)2(H2O)2] (2), [Fe(phen)2(CN)2]·CH3CH2OH·2H2O (3), K[Fe(tp)2]·SO4 (4) (H2pdc = 2,5-Pyridinedicarboxylic acid, H2Imbc = 4,5-Imidazoledicarboxylic acid, phen = 1,10-phenanthroline, tp− = poly(pyrazolyl)borate), were synthesized by hydrothermal and room temperature stirring methods. They were characterized by single crystal X-ray diffraction, surface photovoltage spectroscopy (SPS), field-induced surface photovoltage spectroscopy (FISPS), electron paramagnetic resonance (EPR), UV–Vis absorption spectra (UV–Vis), infrared spectra (IR) and element analysis. The structural analyses indicate that complex (1) is a supramolecule with 2D structure connected by hydrogen bonds. Complex (2) is a supramolecule with hydrogen-bonded 3D structure. Complexes (3) and (4) are both 1D supramolecules connected by hydrogen bonds. The electronic state of central metal Fe(II) ions in complexes (1) and (2) is d6 with FeN2O4 coordination mode, lying in weaker distorted octahedral field. The electronic state of Fe(II) ion in complex (3) is d6 with Fe(CN)2N4 mode in the strong distorted octahedral field. The electronic state of Fe(III) ion in complex (4) is d5 with FeN6 mode, lying in the strong octahedral field. The micro-environment of Fe(II/III) ions in the four complexes is further investigated by EPR. The SPS of four complexes all exhibit photovoltage responses in the range of 300–700 nm. This indicates that they all possess certain photoelectric conversion capability. The effects of component, structure, type of ligands of the complexes, valence state and coordination micro-environment of the central metal ions on the SPS were discussed. Furthermore, the SPS and UV–Vis absorption spectra were interrelated. [Copyright &y& Elsevier]

Abstract: Three Ni(II) coordination complexes [NaNi(NTA)(H2O)] n (1), [Ni(pdc)2(Hppz)2]·H2O (2), [Ni(HL)2] (3) (H3NTA=nitrilotriacetic acid; ppz=piperazine; H2pdc=2,5-pyridinedicarboxylic acid; H2L=2-(1-piperazinl)-succinic acid) were obtained by hydrothermal synthesis method. The structures of the three complexes were determined by single crystal X-ray diffraction. Complex (1) is a 3D coordination polymer bridged by NTA3− groups; complex (2) is a mononuclear complex with ligands of pdc2− and Hppz+, forming a 3D supramolecule via hydrogen bonds; complex (3) is also a mononuclear complex with ligand of HL−, connected into a 3D supramolecule through hydrogen bonds. The photo-electric properties of complexes were investigated by surface photovoltage spectroscopy (SPS). The results of SPS show that the three complexes exhibit obvious photovoltage responses in the range of 300–800nm, which indicates that they all possess certain photo-electric conversion properties. Comparing and analyzing the SPS results of three complexes, it can be found that the component, structure and dimensionality of complex, the category of ligand, the species and number of the direct coordination atoms as well as change of the coordination microenvironment of central metal Ni(II) ion all affect obviously the SPS responses. The SPS and UV–Vis spectra of the complexes were interrelated. [Copyright &y& Elsevier]

Abstract: Five Cd(II)/Zn(II) complexes [Cd(1,2-bdc)(pz)2(H2O)] n (1), [Cd1Cd2(btec)(H2O)6] n (2), [Cd(3,4-pdc) (H2O)] n (3), [Zn(2,5-pdc)(H2O)4]·2H2O (4) and {[Zn(2,5-pdc)(H2O)2]·H2O} n (5) (H2bdc=1,2-benzenedicarboxylic acid, pz=pyrazole, H4btec=1,2,4,5-benzenetetracarboxylic acid, H2pdc=pyridine-dicarboxylic acid) were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, surface photovoltage spectroscopy, XRD, TG analysis, IR and UV–vis spectra and elemental analysis. Structural analyses show that complexes 1–3 are 1D, 2D and 3D Cd(II) coordination polymers, respectively. Complex 4 is a mononuclear Zn(II) complex. Complex 5 is a 3D Zn(II) coordination polymer. The surface photoelectric properties of complexes were investigated by SPS. The results indicate that all complexes exhibit photoelectric responses in the range of 300–600nm, which reveals that they all possess certain photoelectric conversion properties. By the comparative analyses, it can be found that the species and coordination micro-environment of central metal ion, the species and property of ligands affect the intensity and scope of photoelectric response. [Copyright &y& Elsevier]

Highlights: [•] Unexpected isomers were synthesized by 1,3-dipolar cycloaddition reaction of DPNI. [•] The structures of products were solved by single crystal X-ray analysis. [•] A cycloaddition/ring-opening/rearrangement mechanism was proposed. [ABSTRACT FROM AUTHOR]