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1.
The TbIII compound [Tb(tci)(H2O)]n · n(DMF) ( 1 ) [H3tci = tri(2‐carboxythyl)isocyanurate, DMF = N,N′‐dimethylformamide] was synthesized by the reaction of terbium oxide, H3tci, and two drops of concentrated nitric acid in the presence of DMF and H2O. Single crystal X‐ray analysis reveals that it features a three‐dimensional (3D) framework based on infinite –Tb–COO–Tb– chains. The tci ligand in 1 links six different TbIII ions with its two carboxylate groups in μ2‐κ1O;κ2O,O′ mode and the third in μ2‐κ1O;κ1O′ mode. Thermal analysis reveals that it remains high thermal stability until 390 °C. Luminescence investigation shows that it emits characteristic green light of TbIII ions.  相似文献   

2.

A terbium m -methylbenzoate complex with 1,10-phenanthroline, [Tb( m -MBA) 3 phen]·H 2 O has been obtained from ethanol solution, where m -MBA= m -methylbenzoate and phen=1,10-phenanthroline, and its structure determined by X-ray diffraction methods. The unit cell contains binuclear molecules of the title compound. Each Tb 3+ ion is eight-coordinated to one 1,10-phenanthroline molecule, one bidentate carboxylate group and four bridging carboxylate groups, for which the carboxylate groups are bonded to the terbium ion in two modes chelating bidentate and bridging bidentate. Excitation and luminescence data observed at room temperature show that the complex emits very intense green fluorescence under ultraviolet light. Results of thermal analysis indicate that the complex is quite stable to heat.  相似文献   

3.

The title complex has prepared by the reaction of TbL3, Cu(NO3)2 and phen in H2O/EtOH (where L= f -methylacrylato; phen = 1,10-phenanthroline) and its structure determined by X-ray diffraction methods. The complex crystallizes in the triclinic space group PI with Z = 1, a = 11.569(2), b = 14.584(3), c = 11.479(2) Å, f = 101.03(2), g = 104.37(2), n = 74.01(1)°, and the structure was refined to R = 0.041 for 6463 observed reflections. The structure contains a discrete tetranuclear CuTbTbCu molecule. Copper(II) and terbium(III) are bridged by three bidentate carboxyl groups with a Tb ··· Cu separation of 3.9059(9) Å. The Tb ion is eight coordinate and exhibits a distorted square antiprism. The Cu ion is five coordinate and has distorted pyramidal geometry.  相似文献   

4.
Two new terbium complexes with aromatic carboxylic acids, [(Tb)2(L1)6(H2O)4] (1) and [(Tb)2(L2)6(H2O)2(DMF)2] (2) (HL1: nicotinic acid; HL2: 4-hydroxybenzoic acid), with different coordination geometries have been synthesized and their crystal structures determined. The luminescence properties of the two complexes, including the phosphorescence lifetime, have been investigated. The effect of a secondary ligand on luminescence of the ternary terbium complex with carboxylic acid and the relationship between luminescence properties and crystal structure, including coordination mode of the carboxyl groups from HL1 and HL2 and coordination mode of a secondary ligand, are discussed.  相似文献   

5.
A complex of 1,1-cyclobutanedicarboxylic acid with terbium was obtained as a pentahydrate. The salt crystallizes in the monoclinic system, space group P21/n with a = 15.885(3), b = 8.489(2), c = 19.189(4)?Å, β = 106.02(3)° and Z = 4. The structure was solved by direct methods and refined to R = 0.0537. The complex forms polymeric chains in which terbium(III) ions are linked by carboxylate bridges. Each terbium cation is surrounded by carboxylate oxygen atoms and two or three water oxygen atoms, giving coordination number 9. The structure is stabilized by a system of hydrogen bonds.  相似文献   

6.
The crystallization of terbium 5,5′‐azobis[1H‐tetrazol‐1‐ide] (ZT) in the presence of trace amounts (ca. 50 Bq, ca. 1.6 pmol) of americium results in 1) the accumulation of the americium tracer in the crystalline solid and 2) a material that adopts a different crystal structure to that formed in the absence of americium. Americium‐doped [Tb(Am)(H2O)7ZT]2 ZT⋅10 H2O is isostructural to light lanthanide (Ce–Gd) 5,5′‐azobis[1H‐tetrazol‐1‐ide] compounds, rather than to the heavy lanthanide (Tb–Lu) 5,5′‐azobis[1H ‐tetrazol‐1‐ide] (e.g., [Tb(H2O)8]2ZT3⋅6 H2O) derivatives. Traces of Am seem to force the Tb compound into a structure normally preferred by the lighter lanthanides, despite a 108‐fold Tb excess. The americium‐doped material was studied by single‐crystal X‐ray diffraction, vibrational spectroscopy, radiochemical neutron activation analysis, and scanning electron microcopy. In addition, the inclusion properties of terbium 5,5′‐azobis[1H‐tetrazol‐1‐ide] towards americium were quantified, and a model for the crystallization process is proposed.  相似文献   

7.
A terbium p-methyl benzoate complex with 1,10-phenanthroline, [Tb(p-MBA)3(Phen)]2 (p-MBA = p-methyl benzoate and Phen = 1,10-phenanthroline), has been prepared and structurally characterized by X-ray diffraction. It crystallizes in triclinic system, space group P \(\bar 1\) with a = 12.8064(12), b = 13.3589(12), c = 19.8277(19) Å, α = 91.668(2)°, β = 97.775(2)°, γ = 106.312(2)°, C72H58N4O12Tb2, M r = 1489.06, V = 3217.6(5) Å3, Z = 2, ρ c = 1.537 g/cm3, μ(MoK α) = 2.246 mm?1, F(000) = 1488, the final R = 0.0622 and wR = 0.0962 for 14128 independent reflections with R int = 0.0843. It consists of two types of crystallographically independent dimeric molecules [Tb(p-MBA)3(Phen)]2 noted as [Tb-1] and [Tb-2]. In the dimeric molecule [Tb-1], each Tb(III) is eight-coordinated with one Phen molecule, two bridging carboxylate groups, and two bidentate chelating carboxylate groups, while in [Tb-2] each Tb(III) is eight-coordinated with one Phen molecule, four bridging carboxylate groups, and one bidentate chelating carboxylate group. The title complex shows intense green luminescence under UV light at room temperature.  相似文献   

8.
A water‐stable luminescent terbium‐based metal–organic framework (MOF), {[Tb(L1)1.5(H2O)] ? 3 H2O}n (Tb‐MOF), with rod‐shaped secondary building units (SBUs) and honeycomb‐type tubular channels has been synthesized and structurally characterized by single‐crystal X‐ray diffraction. The high green emission intensity and the microporous nature of the Tb‐MOF indicate that it can potentially be used as a luminescent sensor. In this work, we show that Tb‐MOF can selectively sense Fe3+ and Al3+ ions from mixed metal ions in water through different detection mechanisms. In addition, it also exhibits high sensitivity for 2,4,6‐trinitrophenol (TNP) in the presence of other nitro aromatic compounds in aqueous solution by luminescence quenching experiments.  相似文献   

9.
A new coordination polymer of terbium tartrate [Tb(H2O)3(C4H5O6)(C4H4O6)] has been synthesized and crystallizes in the polar space group P41 with cell constants a = 6.0415(9), b = 6.0415(9), c = 36.516(7) Å, V = 1332.8(4) Å3, Z = 4. The terbium(III) ion of title complex is nine-coordinate through oxygen donors. Four different coordination modes of tartrate occur. This Tb(III) complex exhibits a characteristic luminescence in the visible region upon excitation at 353 nm. The temperature-dependent magnetic properties of the Tb(III) complex were investigated in the temperature range of 2–300 K. Title compound exhibits significant ferroelectric properties at room temperature (remnant polarization 2P r = 0.160 μC cm?2, coercive field 2E c = 44.5 kV cm?1, saturation of the spontaneous polarization P s = 0.176 μC cm?2).  相似文献   

10.
本文合成了配合物Tb(Gly)2Cl3·3H2O,用高精度全自动绝热量热仪在81~378 K温区测定了热容,发现在186.054 K和 244.063 K分别存在固-固相变。对配合物进行TG-DTG分析,推测了可能的热分解机理。通过设计适当的Hess热化学循环,利用溶解反应量热计测定了该配合物在298.15 K的标准摩尔生成焓为 -3109.5±3.1 kJ×mol-1。  相似文献   

11.
The complexes of yttrium and heavy lanthanides with 2,4-dimethoxybenzoic acid of the formula: Ln(C9H9O4)3×nH2O, where Ln=Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), Lu(III) and Y(III), n=2 for Tb(III), Dy(III), Ho(III), Er(III), Tm(III) and Y(III), and n=0 for Yb(III) and Lu(III), have been synthesized and characterized by elemental analysis, IR spectroscopy, themogravimetric studies, as well as X–ray and magnetic susceptibility measurements. The complexes have a colour typical of Ln 3+ salts (Tb, Dy, Tm, Yb, Lu, Y – white, Ho – cream, Er – pink). The carboxylate group in these complexes is a bidentate, chelating ligand. The compounds form crystals of various symmetry. 2,4-Dimethoxybenzoates of Yb(III) and Lu(III) are isostructural. 2,4-Dimethoxybenzoates of yttrium and heavy lanthanides decompose in various ways on heating in air to 1173 K. The hydrated complexes first lose water to form anhydrous salts and then decompose to the oxides of respective metals. The ytterbium and lutetium 2,4-dimethoxybenzoates decompose in one step to form Yb2O3 and Lu2O3. The solubilities of the 2,4-dimethoxybenzoates of yttrium and heavy lanthanides in water and ethanol at 293 K are of the order of: 10–3 and 10–3 –10–2 mol dm–3, respectively. The magnetic moments for the complexes were determined over the range of 77–298 K. They obey the Curie–Weiss law. The results show that there is no influence of the ligand field on the 4f electrons of lanthanide ions. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

12.
The Li, Rb and Cs complexes with the herbicide (2,4‐dichlorophenoxy)acetic acid (2,4‐D), namely poly[[aqua[μ3‐(2,4‐dichlorophenoxy)acetato‐κ3O1:O1:O1′]lithium(I)] dihydrate], {[Li(C8H5Cl2O3)(H2O)]·2H2O}n, (I), poly[μ‐aqua‐bis[μ3‐(2,4‐dichlorophenoxy)acetato‐κ4O1:O1′:O1′,Cl2]dirubidium(I)], [Rb2(C8H5Cl2O3)2(H2O)]n, (II), and poly[μ‐aqua‐bis[μ3‐(2,4‐dichlorophenoxy)acetato‐κ5O1:O1′:O1′,O2,Cl2]dicaesium(I)], [Cs2(C8H5Cl2O3)2(H2O)]n, (III), respectively, have been determined and their two‐dimensional polymeric structures are described. In (I), the slightly distorted tetrahedral LiO4 coordination involves three carboxylate O‐atom donors, of which two are bridging, and a monodentate aqua ligand, together with two water molecules of solvation. Conjoined six‐membered ring systems generate a one‐dimensional coordination polymeric chain which extends along b and interspecies water O—H...O hydrogen‐bonding interactions give the overall two‐dimensional layers which lie parallel to (001). In hemihydrate complex (II), the irregular octahedral RbO5Cl coordination about Rb+ comprises a single bridging water molecule which lies on a twofold rotation axis, a bidentate Ocarboxy,Cl‐chelate interaction and three bridging carboxylate O‐atom bonding interactions from the 2,4‐D ligand. A two‐dimensional coordination polymeric layer structure lying parallel to (100) is formed through a number of conjoined cyclic bridges, including a centrosymmetric four‐membered Rb2O2 ring system with an Rb...Rb separation of 4.3312 (5) Å. The coordinated water molecule forms intralayer aqua–carboxylate O—H...O hydrogen bonds. Complex (III) comprises two crystallographically independent (Z′ = 2) irregular CsO6Cl coordination centres, each comprising two O‐atom donors (carboxylate and phenoxy) and a ring‐substituted Cl‐atom donor from the 2,4‐D ligand species in a tridentate chelate mode, two O‐atom donors from bridging carboxylate groups and one from a bridging water molecule. However, the two 2,4‐D ligands are conformationally very dissimilar, with one phenoxyacetate side chain being synclinal and the other being antiperiplanar. The minimum Cs...Cs separation is 4.4463 (5) Å. Structure extension gives coordination polymeric layers which lie parallel to (001) and are stabilized by intralayer water–carboxylate O—H...O hydrogen bonds.  相似文献   

13.
A binuclear terbium(III) complex of N-(2-pyridinyl)ketoacetamide (HL) was synthesized and its crystal structure determined. Each terbium(III) binds to one N,O-bidentate HL, one O,O-bidentate L and two N,μ-O,O-tridentate bridging L ligands; the coordination polyhedron is a distorted square antiprism. The pyridine N and keto O atoms of the binucleating ligand are coordinated to each Tb with the amide O acting as a bridging atom. The adjacent [Tb2(HL)2L4]2+ units are bridged by double C(R)NH…ONO2…HN(R)C hydrogen bonds to form an infinite 1-D chain, and a 2-D layer structure results from a rare near face-to-face π,π-stacking interaction between the pyridine rings of the adjacent chains. The crystal structure analysis reveals that the ligands completely shield the Ln(III) ions. Excited by the absorption band at 370?nm, the Tb(III) complex displays characteristic metal-centered fluorescence while the ligand fluorescence is completely quenched, showing that efficient ligand-to-metal energy transfer (antenna effect) occurs.  相似文献   

14.
Effective detection of organic/inorganic pollutants, such as antibiotics, nitro‐compounds, excessive Fe3+ and MnO4?, is crucial for human health and environmental protection. Here, a new terbium(III)–organic framework, namely [Tb(TATAB)(H2O)]?2H2O ( Tb‐MOF , H3TATAB=4,4′,4′′‐s‐triazine‐1,3,5‐triyltri‐m‐aminobenzoic acid), was assembled and characterized. The Tb‐MOF exhibits a water‐stable 3D bnn framework. Due to the existence of competitive absorption, Tb‐MOF has a high selectivity for detecting Fe3+, MnO4?, 4‐nirophenol and nitroimidazole (ronidazole, metronidazole, dimetridazole, ornidazole) in aqueous through luminescent quenching. The results suggest that Tb‐MOF is a simple and reliable reagent with multiple sensor responses in practical applications. To the best of our knowledge, this work represents the first TbIII‐based MOF as an efficient fluorescent sensor for detecting metal ions, inorganic anions, nitro‐compounds, and antibiotics simultaneously.  相似文献   

15.
Rare earth complex Tb(DPC)22H2O was synthesized by introducing Pyridine-2,6-dicarboxylic acid(H2DPC) as the ligand and characterized by UV, fluorescent and infrared spectra as well as elemental analysis. The complex exhibited ligand-sensitized green emission, and it has the higher sensitized luminescent efficiency and longer lifetime. The effect and mechanism of the ligand (H2DPC) on the luminescence properties of terbium complex was discussed. In device ITO/PVK/Tb(DPC)22H2O/Al, Tb3+ may be excited by intramolecular energy transfer from ligand as observed by electroluminescence. The main emitting peak at 545 nm can be attributed to the transition of 5D47F5 of Tb3+ ion and this process results in the enhancement of green emission from electroluminescence device.  相似文献   

16.
A new germanium complex, cis‐[Ge(pyca)2(OH)2]?2 H2O ( 1 ; pyca=pyridine‐2‐carboxylato), was synthesized by the reaction of [Ge(acac)2Cl2] (acac=acetylacetonato=pentane‐2,4‐dionato) with potassium pyridine‐2‐carboxylate (Kpyca) in H2O/THF. According to the single‐crystal X‐ray diffraction analysis, each Ge‐atom of 1 is coordinated by two pyca ligands and two OH? groups (Fig. 1). These molecules are bonded to each other via a system of H‐bonds resulting in a sheet‐like structure (Fig. 2). The complex is decomposed during heating with stepwise mass loss and formation of GeO2 as final product (Fig. 3).  相似文献   

17.
The two‐dimensional polymeric structures of the caesium complexes with the phenoxyacetic acid analogues (4‐fluorophenoxy)acetic acid, (3‐chloro‐2‐methylphenoxy)acetic acid and the herbicidally active (2,4‐dichlorophenoxy)acetic acid (2,4‐D), namely poly[[μ5‐(4‐fluorophenoxy)acetato][μ4‐(4‐fluorophenoxy)acetato]dicaesium], [Cs2(C8H6FO3)2]n, (I), poly[aqua[μ5‐(3‐chloro‐2‐methylphenoxy)acetato]caesium], [Cs(C9H8ClO3)(H2O)]n, (II), and poly[[μ7‐(2,4‐dichlorophenoxy)acetato][(2,4‐dichlorphenoxy)acetic acid]caesium], [Cs(C8H5Cl2O3)(C8H6Cl2O3)]n, (III), are described. In (I), the Cs+ cations of the two individual irregular coordination polyhedra in the asymmetric unit (one CsO7 and the other CsO8) are linked by bridging carboxylate O‐atom donors from the two ligand molecules, both of which are involved in bidentate chelate Ocarboxy,Ophenoxy interactions, while only one has a bidentate carboxylate O,O′‐chelate interaction. Polymeric extension is achieved through a number of carboxylate O‐atom bridges, with a minimum Cs...Cs separation of 4.3231 (9) Å, giving layers which lie parallel to (001). In hydrated complex (II), the irregular nine‐coordination about the Cs+ cation comprises a single monodentate water molecule, a bidentate Ocarboxy,Ophenoxy chelate interaction and six bridging carboxylate O‐atom bonding interactions, giving a Cs...Cs separation of 4.2473 (3) Å. The water molecule forms intralayer hydrogen bonds within the two‐dimensional layers, which lie parallel to (100). In complex (III), the irregular centrosymmetric CsO6Cl2 coordination environment comprises two O‐atom donors and two ring‐substituted Cl‐atom donors from two hydrogen bis[(2,4‐dichlorophenoxy)acetate] ligand species in a bidentate chelate mode, and four O‐atom donors from bridging carboxyl groups. The duplex ligand species lie across crystallographic inversion centres, linked through a short O—H...O hydrogen bond involving the single acid H atom. Structure extension gives layers which lie parallel to (001). The present set of structures of Cs salts of phenoxyacetic acids show previously demonstrated trends among the alkali metal salts of simple benzoic acids with no stereochemically favourable interactive substituent groups for formation of two‐dimensional coordination polymers.  相似文献   

18.
Abstract

The structures of isomorphic Tb(III) and Ho(III) complexes with 2,6-dihydroxybenzoic acid of formula [Tb(C7H5O4] 2H2O and [Ho(C7H5O4)3 4H2O] 2H2O has been determined by X-ray diffraction and refined to a residual R = 0.030 for 5376 observed reflections and R = 0.0284 for 5660 observed reflections, for Tb(III) and Ho(III) complexes, respectively. Crystals are triclinic, space group P1 with a= 10.748(2), b=11.309(2), c = 12.452(2)Å, α = 82.28(3), ? = 73.05(5), γ = 68.27(3)° for Tb(III) and a= 10.731(2), b=11.269(2), c = 12.436(2)Å, α = 82.25(3), β = 72.92(3), γ = 68.46(3)° for Ho(III).

In the structure of these monomelic complexes the metal ions are coordinated by oxygen atoms of one bidentate chelating and two monodentate carboxylate groups and four molecules of water. Tb-O distances are in the range 2.323(3)-2.506(3) Å and Ho-0 2.297(3)-2.486(3) Å. The crystal structure, consisting of discrete units of neutral complexes with two molecules of water of crystallization is stabilized by intra-and intermolecular hydrogen bonds.  相似文献   

19.
It is found that M(AmH)2(3,5-DNB)4·8H2O compounds (where M(II) = Co, Ni; AmH is piperidine PipH = (C5H10NH2)+ or diethylamine DaH = (C4H10NH2)+ cations; 3,5-DNB = (C7H3N2O6) is the dinitrobenzoic acid anion) are isotypic. The structure of the Ni(PipH)2(3,5-DNB)4·8H2O single crystal is studied. The crystals have a monoclinic system, P21/n space group, Z = 2, a = 6.7694(3) ?, b = 16.0746(6) ?, c = 23.1250(9) ?, β = 97.794(1)°, V = 2493.1(2) ?3, T = 153 K. The final value R(F) = 0.0407 was obtained for 8191 independent reflections with I> 2σ(I). The structural units of the compound studied are as follows: [Ni(OH2)6]2+ complex hexaaquacation, two (PipH)+ cations, four (3,5-DNB) anions, and two molecules of water of crystallization with the structural formula [Ni(OH2)6](PipH)2(3,5-DNB)4·2H2O. Similar compounds of Ni(II) and Co(II) are isostructural.  相似文献   

20.
王瑞芬  王淑萍  石士考  张建军 《结构化学》2004,23(11):1300-1304
1 INTRODUCTION The photoactive lanthanide organic complexessuch as europium and terbium chelating with ?-dike-tones, macrocyclic ligands and a number of polya-mino carboxylates, are of both fundamental and tech-nological interest due to their intense…  相似文献   

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