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1.
A series of pyrazole-bridged heterometallic 3d-4f complexes, [CuDy(ipdc)2(H2O)4] · (2H2O)(H3O+) (1) and [CuLn(pdc)(ipdc)(H2O)4] · H3O+ (Ln = Ho (2), Er (3), Yb (4); H3ipdc = 4-iodo-3,5-pyrazoledicarboxylic acid; H3pdc = 3,5-pyrazoledicarboxylic acid), {[Cu3Ln4(ipdc)6(H2O)16] · xH2O}n (Ln = Sm (5), x = 8.5; Ln = Eu (6), x = 7; Ln = Gd (7), Tb (8), x = 9), have been synthesized and structurally characterized. Ligand H3ipdc was in situ obtained by iodination of ligand H3pdc. Complexes 1-4 are pyrazole-bridged heterometallic dinuclear complexes, and 2-4 are isostructural. Complexes 5-8 are isostructural and comprised of an unusual infinite one-dimensional tape-like chain based on pyrazole-bridged heterometallic dinuclear units. The magnetic properties of compounds 1-4, 7 and 8 have been investigated through the magnetic measurement over the temperature range of 1.8-300 K.  相似文献   

2.
Two novel lanthanide(III) two-dimensional (2D) coordination polymers [Ln2(PDC)2(OH)2(H2O)2] · H2O (Ln = Eu (1) and Tb (2), H2PDC = pyridine-3,4-dicarboxylic acid) have been prepared under hydrothermal conditions and characterized by elemental analysis, IR, TGA and single-crystal X-ray diffraction. Compounds 1 and 2 crystallize in the triclinic system, space group , they are isostructural and exhibit the same two-dimensional topological network constructed by PDC-connected Ln-O-Ln double chains. Photoluminescence properties of the compounds 1 and 2 have been investigated in the solid state at room temperature.  相似文献   

3.
Four lanthanide coordination polymers, [{Ln2(bpdc)3(phen)2(H2O)2} · (H2O)6]n (Ln = Sm (1); Eu (2); Gd (3), Tb (4)), were self-assembled from 2,2′-bipyridine-3,3′-dicarboxylic acid (H2bpdc),1,10-phenanthroline(phen) and corresponding lanthanide oxides by hydrothermal synthesis. Compounds 1-4 are found to be isomorphous and isostructural. Single-crystal X-ray diffraction studies show that compounds 1-4 are all of one-dimensional zigzag chain structures and extend to two-dimensional networks through π-π interactions and hydrogen bonds. The pyridyl nitrogen atoms of the 2,2′-bipyridyl unit in the bpdc ligand are uncoordinated in an anti-conformation along the central C-C bond of the ligand. Thermogravimetric analysis of 1-4 showed an obvious thermal stability indicating that the coordination habit of the metal ions with bpdc and phen has an effect on the overall framework. Photoluminescence measurement indicates that compound 2 and compound 4 are strong red and green emitters, respectively.  相似文献   

4.
Three new lanthanide thiostannates [Ln2(en)62-OH)2]Sn2S6 (Ln = Nd (1), Gd (2); en = ethylenediamine) and [Gd(dien)3]2[(Sn2S6)Cl2] (3) (dien = diethylenetriamine) were first synthesized by treating LnCl3 with SnCl4 and S under mild solvothermal conditions. Compounds 1 and 2 are isostructural. They consist of a binuclear lanthanide(III) complex [Ln2(en)62-OH)2]4+ cation and a dimeric [Sn2S6]4− anion. The anion is built up by two SnS4 tetrahedra sharing a common edge. The Nd3+ and Gd3+ ions are in an eight-coordinated environment forming distorted bicapped trigonal prisms. Compound 3 is composed of two monouclear [Gd(dien)3]3+ complex cations, a [Sn2S6]4− anion, and two chlorine ions. The Gd3+ ion has a nine-coordinated environment forming a distorted tricapped trigonal prism. In compounds 1-3, extensive hydrogen bonds are formed leading to three-dimensional networks of anions and cations. The band gaps of 2.42 eV for 1 and 3.17 eV for 2 have been derived from optical absorption spectra. The new lanthanide compounds might be the precursors for ternary lanthanide thiostannates by the heat treatment under nitrogen atmosphere to get rid of organic components.  相似文献   

5.
The synthesis of a series of lanthanide tetracyanoplatinates containing the auxiliary ligands 1,10′-phenanthroline (phen) or 2,2′-bipyridine (bpy) have been carried out by reaction of Ln3+ nitrate salts with phen or bpy and potassium tetracyanoplatinate in solvent systems containing dimethylsulfoxide and dimethylformamide. The use of these solvents has lead to the isolation of [{Ln(DMSO)2(C12H8N2)(H2O)3}2Pt(CN)4](Pt(CN)4)2·2C12H8N2·4H2O (Ln = Eu (Eu-1), Tb (Tb-1), Yb(Yb-1)), [Ln(DMF)3(C12H8N2)(H2O)2NO3]Pt(CN)4 (Ln = La (La-2), Eu (Eu-2), Tb (Tb-2)), and [Ln(DMF)3(C10H8N2)(H2O)2NO3]Pt(CN)4 (Ln = La (La-3), Sm (Sm-3), Eu (Eu-3), Tb (Tb-3)) in the form of single crystals. Single-crystal X-ray diffraction has been used to investigate their structural features. The use of DMSO versus DMF as the solvent results in markedly different structural features. Eu-1 contains [{Eu(DMSO)2(C12H8N2)(H2O)3}2Pt(CN)4]2+ complex cations where the two Eu3+ centers are linked by a trans-bridging Pt(CN)42− anion to form a dimeric lanthanide complex cation. An additional uncoordinated Pt(CN)42− anion balances charge. Eu-2 and Eu-3 consist of zero-dimensional salts with [Eu(DMF)3(C12H8N2)(H2O)2(NO3)]2+ or [Eu(DMF)3(C10H8N2)(H2O)2(NO3)]2+ complex cations, respectively, and only non-coordinated Pt(CN)42− anions. Photoluminescence measurements illustrate that the Eu3+ and Tb3+ compounds for all three structure types display enhanced emission due to intramolecular energy transfer from the coordinated cyclic amines.  相似文献   

6.
By the “metalloligand” strategy, two new 3d-4f heterometallic metal-organic frameworks (MOFs), {[Ln2Cu3(IDA)6] · 1.5H2O}n [Ln = Tb (1) and Dy (2); H2IDA = iminodiacetate acid], had been prepared. X-ray crystal structure analyses show that 1 and 2 possess of 3D frameworks with highly ordered 1D channels along the c axis. The highly stable skeleton and reversible de- and rehydration performance of 1 are demonstrated by thermogravimetric and powder X-ray diffraction analyses, and a low temperature magnetic study of 2 reveals a weak ferromagnetic interaction between the metal ions.  相似文献   

7.
The thiolate complexes of rare earth metals Ln(SR)3 (La, HSR = 2-mercaptothiazoline (1); La, HSR = 2-mercaptobenzoxazole (2); Y, La, Sm, Eu, Tb, Gd, Er, Tm, HSR = 2-mercaptobenzothiazole (3)) were synthesized in 84-97% yield by the reactions of silylamides Ln[N(SiMe3)2]3 with respective thiols. The products were characterized by elemental analysis, IR and UV/Vis spectroscopy. The structures of 3(Eu) and 3(Er) were determined by single-crystal X-ray diffraction. All obtained compounds revealed efficient luminescence in the region 400-550 nm at 293 K assigned to the ligands emission. Besides, the luminescent spectra of thiolates 3 at 77 K displayed the phosphorescent band of the ligand at 550 nm and in the cases of 3(Eu) and 3(Tb) the sets of emissions bands characteristic for Eu3+ and Tb3+ ions.  相似文献   

8.
Reactions of FeII, CoII, NiII, and ZnII salts with 6-quinolinecarboxylic acid (HL) under the hydrothermal conditions afford three monomeric complexes [M(L)2(H2O)4] (M = FeII for 1, CoII for 2, and NiII for 3) and a 1-D polymeric species {[Zn(L)2(H2O)] · H2O}n (4). The crystal structures of the ligand HL and these four complexes have been determined by using the X-ray single-crystal diffraction technique. The results suggest that complexes 1-3 are isostructural, displaying novel 3-D pillar-layered networks through multiple intermolecular hydrogen bonds, whereas in coordination polymer 4, the 1-D comb-like coordination chains are extended to generate a hydrogen-bonded layer, which is further reinforced via aromatic stacking interactions. Solid-state properties such as thermal stability and fluorescence emission of the polymeric ZnII complex 4 have also been investigated.  相似文献   

9.
The reactions of Ln(NO3)3 · xH2O, CoSO4 · 7H2O or ZnSO4 · 6H2O and 2-pyridylphosphonic acid under hydrothermal conditions result in heterometallic phosphonate compounds with formula [Ln2M3(C5H4NPO3)6] · 4H2O (Ln2M3; M = CoII or ZnII; Ln = LaIII, CeIII, PrIII, NdIII, SmIII, EuIII, GdIII, TbIII, DyIII). These compounds are isostructural and crystallize in a chiral cubic space group I213. Each structure contains the {LnO9} polyhedra and {MN2O4} octahedra which are connected by edge-sharing to form an inorganic open-framework structure with a 3-connected 10-gon (10, 3) topology. The nature of LnIII-CoII magnetic interactions in Ln2Co3 is investigated by a comparison with their LnIII-ZnII analogues. It is found that the LnIII-CoII interaction is weak antiferromagnetic for Ln = Ce and ferromagnetic for Ln = Sm, Gd, Tb and Dy. In the cases of Ln = Pr, Nd and Eu, no significant magnetic interaction is observed.  相似文献   

10.
Preparation, crystal structures and magnetic properties of new heterodinuclear CuIIGdIII (1) and CuIITbIII (2) complexes [CuLn(L)(NO3)2(H2O)3MeOH]NO3·MeOH (where Ln = Gd, Tb) with the hexadentate Schiff-base compartmental ligand N,N′-bis(5-bromo-3-methoxysalicylidene)propylene-1,3-diamine (H2L = C19H20N2O4Br2) (0) have been described. Crystal structure analysis of 1 and 2 revealed that they are isostructural and form discrete dinuclear units with dihedral angle between the O1Cu1O2 and O1Gd1/Tb1O2 planes equal to 2.5(1)° and 2.6(1)°, respectively. The variable-temperature and variable-field magnetic measurements indicate that the metal centers in 1 and 2 are ferromagnetically coupled (J = 7.89 cm−1 for 1). Crystal and molecular structure of the Schiff base ligand (0) has been also reported. The complex formation changes the conformation of Schiff base ligand molecule.  相似文献   

11.
Hydrothermal reactions of rare earth ions(III) with a flexible building unit (1,3,4-thiadiazole-2,5-diyldithio)diacetic acid (H2tzda) lead to five novel coordination polymers with 1D chain and 3D network structures, namely, {[Y2(tzda)3(H2O)10] · 5H2O}n (1) and [Ln2(tzda)3(H2O)5]n [Ln = Er (2), Pr (3), Nd (4), Eu (5)]. Compound 1 has one-dimensional ribbon-like chain structure constructed by [Y2(tzda)3] units through the syn-anti bidentate bridging mode of carboxylate groups. Compounds 2-5 possess compact three-dimensional network structures which are made up of [Ln2(tzda)3] (Ln = Er, Pr, Nd and Eu) units bridged by carboxylate groups. In these compounds, the flexible tzda2− ligand is versatile and displays six different coordination fashions to meet the requirement of the coordination preference of the metal center. Furthermore, the magnetic behaviors for 2-5 in the temperature range of 5.0-300 K and photoluminescent property of 5 are significantly investigated in this paper.  相似文献   

12.
The synthesis of a number of lanthanide tetracyanometallate (TCM) compounds have been carried out by reaction of Ln3+ nitrate salts and potassium tetracyanometallates in solvent systems containing dimethylsulfoxide and water. These reactions result in the isolation of three distinct structure types: (1) monoclinic [Ln(DMSO)4(H2O)3M(CN)4](M(CN)4)0.5·2H2O (Ln = Eu, Tb and M = Pd, Pt), (2) orthorhombic {La(DMSO)3(H2O)2(NO3)M(CN)4}·H2O (M = Pd, Pt), and (3) orthorhombic {Ln(DMSO)3(H2O)(NO3)M(CN)4} (Ln = Tb and M = Pd, Pt; Ln = Er, Yb and M = Pt) in the form of single crystals. Single-crystal X-ray diffraction has been used to investigate their structural features. Structure type 1 is a zero dimensional ionic compound with a M/Ln ratio of 1.5:1. It contains coordinated as well as uncoordinated [M(CN)4]2− (M = Pd, Pt) anions and features relatively long platinophilic interactions. Structure types 2 and 3 differ quite drastically from structure type 1, but they are very similar to each other. Both of the latter are one-dimensional in nature due to chains containing linkage of Ln3+ coordination spheres with trans-bridging [M(CN)4]2− anions. These coordination polymers both have a M/Ln ratio of 1:1, a lack of platinophilic interactions, and incorporation of a bidentate NO3 for charge balance. Photoluminescence properties for select Eu3+ and Tb3+ compounds have been investigated. They show characteristic absorption and emission for the Ln3+ ions, but no significant influence of the tetracyanometallate anions.  相似文献   

13.
Six new coordination polymers based on V-shaped linkage 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and transition metal ions, [Co(bpt)(pm)0.5(H2O)]n · 3nH2O (1), [Cu2(bpt)(pm)(H2O)4]n (2), [Co(bpt)(pydc)]n · 2nCHCl3 · nH2O (3), [Cu2(bpt)(pydc)2(H2O)2]n (4), [Cu2(bpt)(pydco)2(H2O)2]n · nH2O (5) and [Cd(bpt)(pydco)]n (6) (H4pm = pyromellitic acid, H2pydc = pyridine-2,6-dicarboxylic acid, H2pydco = pyridine-2,6-dicarboxylic acid N-oxide), have been synthesized under the intervention of various polycarboxylate ligands. Complex 1 exhibits a 3-D 4-connected structure with 1-D nanosized open channels encapsulated lots of water molecules. Complex 2 represents a 2-D grid containing two types of rectangular windows. When pydc and pydco instead of pm, complexes 3 and 6 were obtained with highly undulated 2-D layers. The interlayers of 3 are filled with two kinds of solvent molecules, whereas 6 is a double-layered framework without free molecules. Complexes 4 and 5 consist of two distinct 1-D infinite chains held together to form different 2-D supramolecular networks. Importantly, bpt spacer shows changeful conformational geometries and generates complicated crystalline architectures with the introduction of polycarboxylate ligands. Additionally, thermal stability of complexes 1, 3 and 5, fluorescent properties of 6 and X-ray powder diffraction of 1 have also been investigated.  相似文献   

14.
Three novel N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane dimeric lanthanide complexes, namely, [{H2L}Sm(NO3)3]2·H2O (1), [{H2L}Gd(NO3)3]4·CH3OH (2), [{H2L}Lu(NO3)3]4·H2O (3) (H2L = N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane) and three new N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane 3d-Gd heterodinuclear complexes, namely, [{LCo}(CH3COO)(CH3COOH)Gd(NO3)2] (4), [{LNi(MeOH)2}Gd(NO3)3]·2MeOH (5) and [{(L)Zn(HNO3)}Gd(NO3)3]·NO3·H3O·MeOH (6) have been synthesized and isolated. X-ray crystallographical analysis reveals that complexes 1-3 are isomorphic with unique dimeric topology. Complexes 4-6 are of discrete 3d-4f dinuclear cores. Magnetic properties of complexes 2 and 4-6 are systematically investigated. Complexes 4 and 5 are ferromagnetic, while 2 and 6 are antiferromagnetic.  相似文献   

15.
Hydrothermal synthesis has afforded a family of four coordination polymers containing divalent nickel or cobalt and pendant-arm pyridylcarboxylate ligands. Utilizing 3-pyridylacetic acid and appropriate metal precursors produced [M(3-pyrac)2(H2O)2] phases (M = Co (1); M = Ni (2)), while 3-pyridylpropionic acid generated [M(3-pyrprop)2(H2O)2] coordination polymers (M = Co (3); M = Ni (4)). Single crystal X-ray diffraction revealed that 1-4 all display discrete 2-D layers with (4,4)-topology, anchored via bridging 3-pyridylcarboxylate ligands bearing monodentate carboxylate termini. Intralamellar hydrogen bonding between the aquo ligands and unligated carboxylate oxygen atoms is observed within 1-4. The pseudo 3-D structures of 1-4 are further assembled via stacking of individual neutral layers by interlayer hydrogen bonding. Thermal properties are also discussed.  相似文献   

16.
Four novel topological nets of lanthanide metal-organic frameworks: [Sm2(op)3(H2O)]n (1), {Ln2(op)2(ox)(H2O)4] · H2O}n (Ln = La, 2; Sm, 3), {[La2(mp)2(ox)(H2O)4] · 2H2O}n (4), [La2(op)2(mp)(H2O)4]n (5) (op = o-phthalate, mp = m-phthalate, and ox = oxalate), have been hydrothermally synthesized and characterized. Compound 1 exhibits novel (3,4,5,6)-connected five-nodal two-dimensional net, compound 2 and 3 show the (3,4)-connected V2O5 topologies, compound 4 has the (4,5)-connected topological net, and compound 5 shows the (4,5)-connected four-nodal three-dimensional network. Photoluminescent analyses of 1 and 3 show strong blue emission in the solid state at room temperature.  相似文献   

17.
The reaction of MCl2 · 2H2O (M = Cu, Zn) with 2,3,5,6-tetra(2-pyridyl)pyrazine (tppz) (referred hereafter as L) in 2:1 molar ratio in acetonitrile at room temperature afforded binuclear complexes [M23-L)Cl4] [Cu (1), Zn (2)] where the ligand is bis-tridentate manner. The complexes have been characterized by elemental analyses, FAB-MS, IR, EPR, NMR and electronic spectral studies. Solid state structures of both the [Cu23-L)Cl4] · 5H2O (1), [Zn23-L)Cl4] · H2O (2) have been determined by single crystal X-ray analyses. A well-resolved uudd cyclic water tetramer and water monomer were reported in the crystal host of [Cu23-L)Cl4] · 5H2O (1) and [Zn23-L)Cl4] · H2O (2) showing the contribution of the water cluster to the stability of the crystal host 1 and 2.  相似文献   

18.
Hydrothermal reactions between H4ODPA (2,2′,3,3′-oxydiphthalic acid) and metal ion salts of Ba2+, Cu2+, Zn2+ and Gd3+ afford four novel coordination polymers [Ba(H2ODPA)(H2O)4] · H2O (1), [Cu2(ODPA)(H2O)3] · H2O (2), Zn2(ODPA)(H2O)2 (3) and [Gd(HODPA)(H2O)3.5] · H2O (4), accordingly. These polymers show great differences in regard to their structures and properties originated from the variation of size and coordination geometry of the metal ions. Compound 1 presents puckered achiral layer structure with (4.82) topology with helices, 2 has a 63 topology with copper tetramer as SBUs, 3 has chiral layer with two kinds of helices built up from Zn-binuclear “paddle-wheel” like SBUs, and 4 features a simple 1D helix with opposite chirality. Compound 3 shows obvious fluorescent emissions upon excitation. Compound 2 shows ferromagnetic interactions between CuII centers bridged by carboxylate groups, whereas compound 4 presents weak ferromagnetic interaction between GdIII ions.  相似文献   

19.
Three distinct coordination complexes, viz. {[Cu(μ-L)2] · (H2O)4}n (1), [Ni(L)2(CH3OH)2] (2), and [Zn(L)2(H2O)2] · (H2O)2 (3), have been prepared by the reactions of metal nitrates with isoquinoline-3-carboxylic acid (HL). X-ray single-crystal diffraction suggests that 1 is a 1D chain coordination polymer in which the CuII ions are connected by carboxylates, whereas complexes 2 and 3 represent discrete mononuclear species. In all the cases, the coordination entities are further organized via hydrogen-bonding interactions to generate multifarious supramolecular networks. Remarkably, a well-resolved 1D water morphology is observed for the first time in the crystalline lattice of 1 along [1 0 0], which consists of edge-sharing tetrameric subunits and stabilized by the metal-organic host surroundings.  相似文献   

20.
Reaction of M(OAc)2 (MII = CuII for 1, CoII for 2, and PbII for 3) with pyridine-2,6-dicarboxylic acid (H2pydc) in presence of a dipyridyl spacer 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (bpo) affords three novel metal-organic supramolecular networks [Cu2(bpo)(pydc)2(H2O)3] · 2.75H2O(1), [Co(bpo)(pydc)(H2O)2] · (H2O) (2) and [Pb(pydc)]n (3), which have been structurally determined by single-crystal X-ray diffraction. The dimeric Cu-pydc coordination framework bridged by a bpo spacer in 1 is hydrogen-bonded to four others to result in a two-dimensional (2-D) sheet array. The neutral monomeric molecules in 2 have an ordered 3-D stacking stabilized via hydrogen bonds and significant π-π interactions in the lattice, possessing large porous channels with the inclusion of guest solvates. In coordination polymer 3, the PbII ion takes the unusual distorted capped trigonal prismatic geometry (PbNO6) and each pydc dianion binds to four PbII centres to form a 2-D infinite network. The thermal stabilities of these complexes have also been investigated.  相似文献   

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