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1.
Reaction in water between trivalent lanthanide ions and ctc3− ligand leads to [Ln(ctc)(H2O)2 · 2.5H2O] 3-D molecular networks with Ln = Tb-Yb or Y. These compounds look like molecular precursors for porous solids. Unfortunately, the dehydrated phases are not structurally characterized. We report here the study of the partially dehydrated phases with general formula [Ln(ctc)(H2O)2] with Ln = Tb-Yb or Y obtained by freeze-drying of the corresponding hydrated phases. Their porosity is estimated as well as the luminescent properties of the Tb-containing compound.  相似文献   

2.
Treatment of Ln(NO3)3 · 6H2O with 1, 2-phenylenedioxydiacetic acid (H2PDOA) in ethanol leads to the unusual 1-D double chain complexes {[Ln(PDOA)1.5 (H2O)3] · H2O}n (Ln = Sm (1), Eu (2), Dy (3)), in which the Ln3+ ions are linked by pentadentate and bideatate PDOA ligands in two different directions. The chain looks like a ladder containing two -Ln-O-C-O-Ln- chains and PDOA spacers, which has never been observed in the lanthanide carboxylate complexes, and they exhibit different photoluminescence properties.  相似文献   

3.
Three one-dimensional zinc complexes, namely, [Zn(pzdc) · 3H2O] · H2O (1), [Zn2(pzdc)· 4H2O] · 2.5H2O (2), and [Zn(pzdc)(phen) · 4H2O]n (3) (H2pzdc, pyrazine-2,3-dicarboxylic acid, phen = 1,10-phenanthroline), have been synthesized successfully under hydrothermal condition. X-ray diffraction analyses reveal that complex 1 is a square-wave-like chain and complex 2 shows a 1D ladder-like infinite chain, while complex 3 has 1D zigzag chain structure. In all cases, the Zn(II) centers have octahedral coordination geometries. Through hydrogen bonding (such as O-H···O, O-H···N and C-H···O) and/or π-π stacking interactions, three-dimensional supramolecular networks are constructed in three complexes. Furthermore, the IR, TGA and luminescent properties are also investigated in this work.  相似文献   

4.
New solid complex compounds of La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III) and Gd(III) ions with morin were synthesized. The molecular formula of the complexes is Ln(C15H9O7)3 · nH2O, where Ln is the cation of lanthanide and n = 6 for La(III), Sm(III), Gd(III) or n = 8 for Ce(III), Pr(III), Nd(III) and Eu(III). Thermogravimetric studies and the values of dehydration enthalpy indicate that water occurring in the compounds is not present in the inner coordination sphere of the complex. The structure of the complexes was determined on the basis of UV-visible, IR, MS, 1H NMR and 13C NMR analyses. It was found that in binding the lanthanide ions the following groups of morin take part: 3OH and 4CO in the case of complexes of La, Pr, Nd, Sm and Eu, or 5OH and 4CO in the case of complexes of Ce and Gd. The complexes are five- and six-membered chelate compounds.  相似文献   

5.
Four lanthanide coordination polymers formulated as {[La3L9(H2O)3]EtOH · H2O}n1, {[Pr2L6(H2O)2]HL · H2O}n2, {[Dy2L6(H2O)]0.5HL · H2O}n3 and {[Ho2L6(H2O)]0.5HL · H2O}n4 and HL = trans-2-butenoic acid have been synthesized from the corresponding pure lanthanide oxide and HL acid in water at pH 3. The compounds were characterized by chemical analysis, IR spectroscopy, thermogravimetry, variable-temperature magnetic susceptibility and single crystal X-ray diffraction studies. A common feature in these materials is the presence of two differentiated lanthanide nodes linked by carboxylates into extended chains. These are further connected by inter- and intra-molecular hydrogen-bonds involving ligand and solvate molecules. Weak ferromagnetic interactions appear to be operative in the Dy material.  相似文献   

6.
Five new supramolecular lanthanide coordination polymers with three different structures, {[La2(IA)3(phen)2] · 2H2O}n (1), {[Ln(IA)1.5(phen)] · xH2O}n [x = 1, Ln = Eu (2); x = 0.25, Ln = Dy (3)], and [Ln(IA)1.5(phen)]n [Ln = Er (4); Yb (5)], were prepared by hydro- and solvothermal reactions of lanthanide chlorides with itaconic acid (H2IA) and 1,10-phenanthroline (phen), and structurally characterized by single crystal X-ray diffraction. 1 Comprises 1-D double-chains that are further assembled to a 3-D supramolecular structure via hydrogen bonds and π-π stacks between phen molecules. 2 and 3 have 2-D infinite networks which are further constructed to form 3-D supramolecular architectures with 1-D channels by π-π aromatic interactions. 4 and 5 have 2-D layer structures consisting of three types of rings which are further architectured to form 3-D supramolecular structures by C-H?O hydrogen bonds. The H2IA ligands are all completely deprotonated and exhibit tetra-, penta-, and hexadentate coordination modes in the titled complexes. The high-resolution emission spectrum of 2 shows only one Eu3+ ion site in 2, which is in agreement with the result of X-ray diffraction. And the magnetic property and the thermal stability of 2 were also investigated.  相似文献   

7.
The combination of anhydrous SnCl4 with 18-crown-6 in aqueous conditions results in formation of the non-hydrolysed product [cis-SnCl4(H2O)2] · 18-crown-6 · 2H2O. The X-ray crystal structure shows extensive intermolecular hydrogen bonding involving the cis-octahedral SnCl4(H2O)2 units, the uncoordinated water molecules and the crown ether. Similarly, [2,2,2]cryptand reacts with an aqueous solution formed by adding anhydrous GaCl3 to slightly acidic water, affording [[2,2,2]cryptand + 2H+][GaCl4]2.  相似文献   

8.
Synthesis and spectroscopic characterization of new lanthanide complexes [Ln(QAD)3(EtOH)(H2O)], (Ln = Tb, Eu; HQAD = 1-phenyl-3-methyl-4-adamantylcarbonyl-pyrazol-5-one), [H3O][Tb(QAD)4], [Ln(QAD)3(N-N)] (Ln = Tb, Eu; N-N = 1,10-phenanthroline (Phen), 2,2′-bipyridyl (Bipy), 4,4′-dimethyl-2,2′-bipyridyl (4,4′-Me2Bipy)) are reported. The crystal structures of the proligand HQAD and of complexes [H3O][Tb(QAD)4] and [Tb(QAD)3(4,4′-Me2Bipy)] have been determined. In both complexes the lanthanide ions are in a square antiprismatic environment, the H3O+ cation in the former acid complex being stabilized by H-bonding. Luminescence studies have been performed on selected derivatives.  相似文献   

9.
The mononuclear macrocyclic lanthanide(III) complexes, [Ln(H2L)(H2O)4]Cl3 (Ln = Y, La, Ce, Cu, Tb, Yb, Lu; H2L = H2LA, H2LB, H2LC) were prepared by condensation 3,3′-(3,6-dioxaoctane-1,8-diyldioxy)bis(2-hydroxybenzaldehyde) or 3,3′-(3-oxapentane-1,5-diyldioxy)bis(2-hydroxybenzaldehyde) with 1,5-diamino-3-azamethylpentane or 1,7-diamino-3-azamethylheptane in the presence of LnCl3 · nH2O as templating agent. The asymmetric [1+1] ligands H2LA, H2LB and H2LC contain one smaller or larger N3O2 Schiff base site and one crown-ether like O2O4 or O2O3 site. The preference of the lanthanide ion to reside into the Schiff base or the crown-ether like chamber was investigated in the solid state and in methanol or dimethylsulfoxide solution. It was found that in the solid state or in methanol the lanthanide(III) ion coordinates into the O2On site while in dimethylsulfoxide demetalation and partial metal ion migration from the O2On into the N3O2 chamber occur. The mononuclear lanthanide(III) complexes [Ln(H2L)(H2O)4]Cl3 with the Ln3+ ion in the O2On site have been used as ligands in the synthesis of the heterodinuclear complexes LnLn′(L)(Cl)4 · 4H2O by reaction with the appropriate Ln′(III) chloride in methanol and in the presence of base. The related homodinuclear complexes Ln2(L)(Cl)4 · 4H2O have been prepared by the one-pot condensation of the appropriate precursors in the presence of base and of the lanthanide(III) ion as templating agent.The single-crystal X-ray structure of [Eu(H2LA)(H2O)4]Cl3 · 5H2O has been determined. The europium ion is nine-coordinated in the O2O3 ligand site and bonded to four water molecules and the coordination polyhedron can be described as a square monocapped antiprism.The site occupancy of the different lanthanide(III) ions and the physico-chemical properties arising from the different dinuclear aggregation and/or from the variation of the crown-ether shape have been investigated by IR and NMR spectroscopy, MS spectrometry and SEM-EDS microscopy. In particular, site migration and/or transmetalation reactions, together with demetalation reactions, have been monitored by NMR studies in methanol and dimethylsulfoxide. It was found that these processes strongly depend on the shape of the two coordination chambers, the solvent used and the radius of the lanthanide(III) ions. Thus, these molecular movements can be tuned by changing appropriately these parameters.  相似文献   

10.
The reaction of Ln(III) ions with the precursor [Cu(opba)]2− in DMSO has afforded a series of isostructural compounds of general chemical formula Ln2[Cu(opba)]3(DMSO)6(H2O) · (H2O), where Ln(III) stands for a lanthanide ion and opba stands for ortho-phenylenebis(oxamato). The crystal structure has been solved for the Gd(III) containing compound. It crystallizes in the orthorhombic system, space group Pbn21 (No. 33) with a = 9.4183(2) Å, b = 21.2326(4) Å, c = 37.9387(8) Å and Z = 4. The structure consists of ladder-like molecular motifs parallel to each other. To the best of our knowledge, this is the first Ln(III)Cu(II) coordination polymer family exhibiting the same crystal structure over the whole lanthanide series. The magnetic properties of the compounds have been investigated and the magnetic behavior of the Gd(III) containing compound was studied in more detail.  相似文献   

11.
Reactions in water between the di-sodium salt of amino terepthalic acid (C8H3NO4Na2) and a lanthanide chloride lead to a family of 3D-coordination polymers with general chemical formula [Ln(C8H3NO4)(C8H4NO4), O] where Ln = La-Eu (except Pm) and 8 ? n ? 11. All these compounds are isostructural. High quality single crystals of [Ln(C8H3NO4)(C8H4NO4), nH2O] with Ln = La-Sm (except Pm) and 8 ? n ? 11 have been obtained by slow diffusion in agar-agar gels. The crystal structure has been solved for the Nd-containing compound. This compound crystallizes in the cubic system, space group Ia-3 (no. 206) with a = 26.8056(5) Å. The crystal structure can be described as the juxtaposition of large channels with square cross-section.The channels are filled by highly disordered crystallization water molecules. The dehydration of the compounds by freeze-drying is possible and most of the crystallization water molecules can be removed without destruction of the molecular skeleton. The partially dehydrated compounds have general chemical formula [Ln(abdc)(Habdc), 2H2O] with Ln = La-Eu except Pm. The porosity of the Nd-containing compound has been estimated by computational methods to 2170 m2 g−1. This dehydrated compound reversibly binds water when exposed to wet atmosphere restoring the initial hydrated phase.  相似文献   

12.
In this paper, we report the synthesis and the characterization of a novel series of lanthanide (III) complexes with two potentially hexadentate ligands.The ligands contain a rigid phenanthroline moiety and two flexible hydrazonic arms with different donor atom sets (NNN′N′OO and NNN′N′N″N″, respectively for H2L1 (2,9-diformylphenanthroline)bis(benzoyl)hydrazone and H2L2 (2,9-diformylphenanthroline)bis(2-pyridyl)hydrazone).Both nitrate and acetate complexes of H2L1 with La, Eu, Gd, and Tb were prepared and fully characterized, and the X-ray crystal structure of the complex [Eu(HL1)(CH3 COO)2] · 5H2O is presented.The stability constants of the equilibria Ln3+ + H2L1 = [Ln(H2L1)]3+ and Ln3+ + (L1)2− = [Ln(L1)]+ (Ln = La(III), Eu(III), Gd(III), and Tb(III)) are determined by UV spectrophotometric titrations in DMSO at t = 25 °C. The nitrate complexes of H2L2 with La, Eu, Gd and Tb were also synthesized, and the X-ray crystal structures of [La(H2L2)(NO3)2(H2O)](NO3), [Eu(H2L2)(NO3)2](NO3) and [Tb(H2 L2)(NO3)2](NO3) are discussed.  相似文献   

13.
Two lanthanide(III) complexes with l-glutamate ligands [{Ln2(l-Glu)2(H2O)8} · 4(ClO4) · 2.5H2O]n (Ln = Gd (1), Eu (2)) have been prepared and characterized by single-crystal X-ray diffraction. The compounds are isomorphous with infinite cationic 2D layers stacked together by secondary bonds. The building blocks are slightly different non-centrosymmetric dinuclear units placed in alternating layers, the resulting structures thus containing four non-equivalent Ln metal sites. The dinuclear units contain a fourfold bridge, two in the η112 and two in the η212 modes, from two α- and two γ-carboxylates of four different l-Glu residues, respectively.  相似文献   

14.
The complexes of 2-[2-(diphenylphosphoryl)prop-2-yl]-1,8-naphthyridine (L) with lanthanide nitrates Ln(NO3)3 (Ln = Nd, Eu, Lu) were investigated to elucidate the coordination ability of a novel type of potentially tridentate ligands - phosphorylalkyl substituted naphthyridines. The X-ray crystal structures of [NdL3]3+ · 3(NO3) · MeCN (1), [EuL3]3+ · 3(NO3) · [Eu(NO3)3 · 4H2O] · MeCN (2), and [LuL3]3+ · 3(NO3) · [Lu(NO3)3 · 3H2O] · 2 MeCN · 0.5 H2O (3) are reported together with their IR and Raman spectra. All the compounds studied contain isostructural [LnL3]3+ cations and three NO3 counterions. Coordination of each L appears to be O,N,N tridentate-cyclic and coordination number of Ln is nine. Vibrational spectra of 1-3 are also compared with that of free ligand and model compounds.  相似文献   

15.
Four one-dimensional coordination polymers, [Ln(H2O)4(HTDA)(H2TDA)] · H2O [Ln = Sm (1) and Eu (2)]; (H3TDA = 1H-[1,2,3]-triazole-4,5-dicarboxylic acid), [Ln(H2O)4(HTDA)] · (H2TDA) · H2O [Ln = Tb (3) and Dy (4)] were prepared and characterized by IR, elemental analysis, PXRD and single-crystal X-ray diffraction. The powder and single-crystal X-ray crystallographic studies of 1-4 reveal that all compounds are one-dimensional zigzag chain structures. Luminescent studies reveal that they are potential luminescent materials. Moreover, in solution, the emission intensity of 2 increases upon the addition of Ca2+ ions, while introduction of other metal ions leads to either unchanged or decreased intensity, which indicates that 2 may be applied as a promising Ca2+-ion-selective luminescent probe. The basic magnetic properties of 1-4 were also studied.  相似文献   

16.
The syntheses and X-ray crystal structures of the Eu, Gd, Dy, Ho, and Er nitrate complexes of the pentadentate ligand 2,6-diacetylpyridine bis acetic acid hydrazone, or H2dapaah, are reported. The complexes can be divided into 3 groups depending on the number of water molecules per metal ion. The Ln · 4H2O complexes with Eu, Gd and Dy are isomorphous, with the Ln ion being 10 coordinate. The Ln · 6H2O group includes Ho and Er, where the cation is 9 coordinate. The final complex Gd · 5H2O is 10 coordinate like the Eu, Gd and Dy complexes, but the additional water molecule has stabilized an ordered crystal. The bond valence sum method has been used to analyze the bonding in the complexes and has suggested that bond valence equalization in three dimensions may be an important concept.  相似文献   

17.
Five isostructural compounds of lanthanide with isonicotinate ligand, formula as [Ln(IN)2(H2O)4](NO3) (Ln = La, Nd, Eu, Tb and Er, 15, IN = isonicotinate), were synthesized under hydrothermal conditions by tuning the pH level and the ratio of lanthanide with isonicotinic acid. These compounds were characterized by single-crystal X-ray structure analysis, elemental analysis, IR and TG-DTA. In five compounds, the adjacent eight-coordination lanthanide centers were linked together through the bidentate bridging carboxylate groups of isonicotinate ligands to generate infinite chain structures which were further interconnected to form 3D supramolecular networks via the OW-H···N (nitrogen atom came from isonicotinate ligands) and OW-H···O (oxygen atom came from nitrate) hydrogen bonds. Compounds 3 and 4 show strong red and green emission, corresponds to 5D07F2 transition of Eu3+ ions and 5D47F5 transition of Tb3+ ions, respectively.  相似文献   

18.
The new hydrazinium lanthanide metal complexes of 2-pyrazinecarboxylic acid of the formulae (N2H5)2[Ln(pyzCOO)5] · 2H2O (1), where Ln = La or Ce and (N2H5)3[Ln(pyzCOO)4(H2O)] · 2NO3 (2), where Ln = Pr, Nd, Sm or Dy have been synthesized by the addition of an aqueous solution of corresponding metal nitrate hydrates to an aqueous mixture of carboxylic acid and hydrazine hydrate in an appropriate ratios. The structure of (N2H5)2[La(pyzCOO)5] · 2H2O (1a) and (N2H5)3[Nd(pyzCOO)4(H2O)] · 2NO3 (2a) have been determined from single crystal X-ray analysis. Coordination numbers from six to twelve have been established in lanthanide compounds but ten coordination appears rarely. This work reports the first ten coordinated hydrazinium lanthanide complexes with carboxylate anions. The structure contains lanthanum ions joined by 2-pyrazinecarboxylate groups forming two-dimensional sheets parallel to (0 0 1) plane. 2a is monomeric in nature and the structure comprises of N2H5+ cations, [Nd(pyzCOO)4(H2O)] and anions. The neodymium is nine coordinated with four pyzCOO lignads, bidentate (N,O) to the metal and the lone water molecule completes the coordination sphere and the sheets like pattern in all are interlinked via multiple hydrogen bonds leading to three dimensional structure.  相似文献   

19.
Pyrazole-3,5-dicarboxylate-bridged dinuclear ruthenium(II) and osmium(II) complexes of 2,2-bipyridine of composition [(bpy)2Ru(pzdc)Ru(bpy)2](ClO4) · H2O (1) and [(bpy)2Os(pzdc)Os(bpy)2](ClO4) · H2O (2) have been obtained in high yield and have been separated to their homochiral (ΛΛ/ΔΔ) rac (1a, 2a) and heterochiral (ΛΔ/ΔΛ) meso (1b, 2b) diastereoisomers. The distinctive structural features of these diastereoisomers have been characterized by 1-D and 2-D 1H NMR spectroscopy. The X-ray crystal structure of rac-[(bpy)2Os(pzdc)Os(bpy)2](ClO4) · H2O (2a) has been determined. The electrochemical and electronic spectral studies have established that there remain difference in properties and hence difference in intermetallic communication between the diastereoisomeric forms in each case.  相似文献   

20.
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.  相似文献   

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