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1.
R. Łyszczek 《Journal of Thermal Analysis and Calorimetry》2008,91(2):595-599
The complexes of lanthanides(III) with hemimellitic acid (1,2,3-benzenetricarboxylic acid, H3btc) of the formula Ln(btc)·nH2O, where Ln=lanthanide(III) ion and n=2?6 were prepared and characterized by elemental analysis, infrared spectra, X-ray diffraction patterns and thermal analysis. The IR spectra of the complexes indicate coordination of lanthanides(III) through all carboxylate groups. The complexes of La(III), Ce(III), Pr(III) and Er(III) are amorphous. On heating in air atmosphere all complexes lose water molecules and next anhydrous compounds decompose to corresponding metal oxides. 相似文献
2.
《Journal of Analytical and Applied Pyrolysis》2010,87(2):239-244
The characterisation of light lanthanide(III) complexes with pyridine-3,5-dicarboxylic acid of the formula Ln2pdc3·nH2O where Ln denotes lanthanides from La to Gd, pdc = C7H5NO42−; n = 6 for Ce(III), n = 7 for Pr(III) and Sm(III), n = 8 for La and n = 13 for Nd(III), Eu(III) and Gd(III) was performed by the thermal analysis TG-DTA and the simultaneous infrared evolved gas analysis TG-FTIR. Heating of the crystalline complexes resulted in the dehydration process at first. Next, dehydrated compounds decompose releasing of CO2, CO, CH4 and hydrocarbons. Free pyridine molecules were detected only in the gaseous products of lanthanum(III) complex decomposition. 相似文献
3.
Renata ?yszczek 《Journal of Thermal Analysis and Calorimetry》2012,108(3):1101-1110
In this study, new series of lanthanide 4,4??-oxybis(benzoates) of the general formula Ln2oba3·nH2O, where Ln = lanthanides from La(III) to Lu(III), oba?=?C12H8O(COO) 2 2? and n?=?3?C6, has been prepared under hydrothermal conditions. The compounds were characterized by elemental analysis, infrared spectroscopy, X-ray diffraction patterns measurements and different methods of thermal analysis (TG, DSC, and TG-FTIR). In addition, photoluminescence properties of the selected complexes have been investigated. Crystalline compounds are isostructural in the whole series. Both carboxylate groups are deprotonated and engaged in the coordination of Ln(III) ions. Heating of the complexes leads to the dehydration and next decomposition processes. Although of the same structure, the removal of water molecules proceeds in different ways. In the nitrogen atmosphere, they decompose releasing water, carbon oxides and phenol molecules. The complexes of Eu(III), Tb(III) and Dy(III) exhibit photoluminescence in the visible range, whereas the compounds of Nd(III) and Yb(III) in the near-infrared region upon excitation by UV light. 相似文献
4.
Zofia Rzączyńska Anna Danczowska-Burdon Justyna Sienkiewicz-Gromiuk 《Journal of Thermal Analysis and Calorimetry》2010,101(2):671-677
Pyridine-2,5-dicarboxylic acid, known as isocinchomeric acid is one of six isomers containing two carboxylic groups. Light
lanthanide (III) complexes with pyridine-2,5-dicarboxylic acid with general formula Ln2L3·nH2O, where n = 8, 9, were obtained. Their thermal and spectroscopic properties were studied. Sodium salt was obtained as Na2L·H2O. Hydrated complexes of La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III) and Gd(III) are stable to 313–333 K, whereas
Na2L·H2O is stable to about 333 K. Dehydration process for all compounds runs in one stage, next they decompose into appropriate
lanthanide oxalates, oxocarbonates carbonates and finally to metal oxides. Bands of νCOOH vibrations at 1736 and 1728 cm−1 disappear on complex spectra and νas and νs of COO− groups appear thus indicating that complexation process took place. 相似文献
5.
The complexes of yttrium and heavy lanthanides with 3,4-dimethoxybenzoic acid of the formula: Ln(C9 H9 O4 )3 ×n H2 O, where Ln =Y(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III) and Lu(III), and n =4 for Tb(III), Dy(III), n =3 for Ho(III), and n =0 for Er(III), Tm(III), Yb(III), Lu(III) and Y(III) have been prepared and characterized by elemental analysis, IR spectroscopy,
thermogravimetric and magnetic studies and X-ray diffraction measurements. The complexes have colours typical of Ln3+ ions (Ho - cream, Tb, Dy, Yb, Lu, Y - white, Er - salmon). The carboxylate group in these complexes is a symmetrical, bidentate,
chelating ligand. They are crystalline compounds characterized by various symmetry. On heating in air to 1273 K the hydrated
3,4-dimethoxybenzoates decompose in two steps while those of anhydrous only in one stage. The tetrahydrates of Tb and Dy and
trihydrate of Ho 3,4-dimethoxybenzoates are firstly dehydrated to form anhydrous salts that next are decomposed to the oxides
of the respective metals. The complexes of Er, Tm, Yb, Lu and Y are directly decomposed to the oxides of the appropriate elements.
The solubility in water at 293 K for yttrium and heavy lanthanides is in the order of 10-4 -10-3 mol dm-3 . The magnetic moments of the complexes were determined over the range 77–298 K. They obey the Curie-Weiss law. The values
of μeff calculated for all compounds are close to those obtained for Ln3+ by Hund and van Vleck. The results show that there is no influence of the ligand field on 4f electrons of lanthanide ions
in these polycrystalline compounds and 4f electrons do not take part in the formation of M-O bonding.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
Renata ?yszczek Zofia Rz?czyńskaAlina Kula Agnieszka G?adysz-P?aska 《Journal of Analytical and Applied Pyrolysis》2011,92(2):347-354
The lanthanide 2,6-naphthalenedicarboxylates series of the formulas Ln2(ndc)3·nH2O, where Ln = lanthanides from La(III) to Lu(III); ndc - C10H6(COO)22−; n = 4, 4.5 or 5 have been prepared by the precipitation method. All obtained products were examined and characterized by elemental analysis, FTIR spectroscopy, simultaneous thermal analyses TG-DSC and TG-FTIR, X-Ray diffraction patterns as well as luminescence measurements. The crystalline compounds form three isostructural groups: Ce-Sm; La and Eu-Dy; Ho-Lu. In all complexes, the ndc2− ligand appears in the deprotonated form. Heating of the complexes resulted in the multi-steps decomposition process. The dehydration process leads to the formation of stable crystalline Ln2ndc3 compounds which further decompose to the corresponding lanthanide oxides (air atmosphere). In argon atmosphere they decompose with releasing of water, carbon oxides and naphthalene molecules. The luminescence properties of Eu(III), Nd(III), Tb(III) and Er(III) complexes were investigated. The complexes of Eu(III) and Tb(III) emitted red and green light when excited by ultraviolet light whereas Nd(III) and Er(III) display emissions in the NIR region. 相似文献
7.
《Journal of Coordination Chemistry》2012,65(17):2796-2803
Direct reaction of pyridine-3,5-dicarboxylic acid (H2PDA) and oxalic acid (H2ox) with Ln(ClO4)3 · nH2O under hydrothermal conditions gave three 3-D coordination networks, [Ln(PDA)(ox)0.5(H2O)2] · H2O [Ln = La(1), Nd(2), and Eu(3)]. The complexes were characterized by elemental analysis (EA), X-ray single-crystal diffraction, infrared spectroscopy (IR), and thermogravimetric analysis (TGA). Single crystal X-ray diffractions shows that the compounds are isomorphous and have 3-D framework structures, in which pyridine-3,5-dicarboxylates (PDA2?) link lanthanides to give 2-D layers, which are further fabricated into a 3-D network via bis-bidentate oxalate bridging. Luminescence of 3 is investigated. 相似文献
8.
A. G. Matveeva E. I. Matrosov G. V. Bordin S. V. Matveev Z. A. Starikova P. V. Petrovskii E. E. Nifant’ev 《Russian Journal of Inorganic Chemistry》2006,51(11):1735-1742
A new bisphosphoryl ligand, 2,4-bis(diphenylphosphorylmethyl)mesitylene (L1), has been synthesized. Upon the interaction of L1 with lanthanide nitrates, stable mononuclear chelates [Ln(L1) n (NO3)3] (Ln = Ce(III), Nd(III), Er(III); n = 1, 2) were obtained. The structure of the complexes in solid state and in solution was studied by vibrational (IR and Raman) spectroscopy, X-ray diffraction, and conformational (molecular mechanics) analysis. 相似文献
9.
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
10.
The complexes of heavy lanthanides and yttrium with 2,3-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), Y(III), and n=2 for Tb(III), Dy(III), Ho(III), Y(III), n=1 for Er(III), Tm(III), n=0 for Yb(III) and Lu(III) have been synthesized and characterized by elemental analysis, ir spectroscopy, thermogravimetric
studies and x-ray diffraction measurements. The complexes have colours typical for Lnł3+ ions (Tb(III), Dy(III), Tm(III), Yb(III), Lu(III), Y(III) - white; Ho(III) - cream and Er(III) - salmon). the carboxylate
groups in these complexes are a symmetrical, bidentate, chelating ligand or tridentate chelating-bridging. they are isostructural
crystalline compounds characterized by low symmetry. On heating in air to 1273 k the 2,3-dimethoxybenzoates of heavy lanthanides
and yttrium decompose in various ways. The complexes of Tb(III), Dy(III), Ho(III), Er(III), Tm(III) and Y(III) at first dehydrate
to form anhydrous salts which next are decomposed to the oxides of the respective metals. 2,3-dimethoxybenzoates of Yb(III)
and Lu(III) are directly decomposed to oxides. When heated in nitrogen the hydrates also dehydrate in one step to form the
anhydrous complexes that next form the mixture of carbon and oxides of respective metals or their carbonates. The solubility
of the yttrium and heavy lanthanide 2,3-dimethoxybenzoates in water at 293 k is of the order of 10-2 mol dm-3.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
Structural, thermal, and spectral investigations of the lanthanide(III) biphenyl-4,4′-dicarboxylates
Justyna Sienkiewicz-Gromiuk Zofia Rzączyńska 《Journal of Thermal Analysis and Calorimetry》2013,112(2):877-884
The lanthanide biphenyl-4,4′-dicarboxylates (bpdc) series of the general formulae Ln2(bpdc)3·nH2O, where Ln = lanthanides from La(III) to Lu(III); bpdc = C12H5(COO) 2 2? ; n = 4, 5 or 6 have been obtained by the conventional precipitation method. All prepared complexes were characterized by elemental analysis, simultaneous thermal analyses thermogravimetric-differential scanning calorimetry (TG–DSC) and TG–FT-IR, FT-IR, and FT-Raman spectroscopy as well as X-ray diffraction patterns measurements. In the whole series of analyzed complexes the bpdc2? ligand is completely deprotonated. In view of that, four carboxylate oxygen atoms are engaged in the coordination of Ln(III) ions. The synthesized compounds are polycrystalline and insoluble in water. They crystallize in the low symmetry crystal systems, like monoclinic and triclinic. Heating in the air atmosphere resulted in the multi-steps decomposition process, namely endothermic dehydration and strong exothermic decomposition processes. The dehydration process leads to the formation of stable anhydrous Ln2bpdc3 compounds which subsequently decompose to the corresponding lanthanide oxides. 相似文献
12.
Nancy Redman-Furey Kate Poiesz James Miller Carol Grundner 《Journal of Thermal Analysis and Calorimetry》2010,102(2):633-639
The thermal behavior of [Ca(H2O)3(2,3-pydcH)2]
n
(I), [Cd(H2O)3(2,3-pydc)]
n
(II), and [Cd(H2O)6][Cd(2,3-pydcH)3]2 (III) complexes with pyridine-2,3-dicarboxylic acid was monitored by TG, DTG, and DSC analysis, where 2,3-pydcH—mono deprotonated
pyridine-2,3-dicarboxylic acid and 2,3-pydc—doubly deprotonated dicarboxylate anion. Thermal decomposition of these compounds
go through one or two dehydratation stages, followed by the loss of organic matter. The final decomposition products are found
to be the corresponding metal oxides. The possible scheme of destruction of the complexes have been used to reveal the relationships
between stability and molecular structure. 相似文献
13.
《Journal of Coordination Chemistry》2012,65(12):1862-1874
The synthesis and characterization of lanthanide(III) complexes with the Schiff-base hydrazone, o-hydroxyacetophenone-7-chloro-4-quinoline, (HL) are reported. The complexes were characterized by different physicochemical methods: mass spectrometry, 1H NMR, 13C NMR, and IR, UV-visible, molar conductance and magnetic studies. They have the stoichiometry [Ln(L)2(NO3)]·nH2O where Ln = La(III), Pr(III), Nd(II), Sm(III), Eu(III) and n = 1–3. The spectra of the complexes were interpreted by comparison with the spectrum of the free ligand. The Schiff-base ligand and its metal complexes were tested against one stain Gram +ve bacteria (Staphylococcus aureus), Gram ?ve bacteria (Escherichia coli), and Fungi (Candida albicans). The tested compounds exhibited high antimicrobial activities 相似文献
14.
Wiesława Ferenc B. Cristóvão J. Sarzyński Maria Wojciechowska 《Journal of Thermal Analysis and Calorimetry》2007,88(3):877-883
4-Chloro-2-methoxybenzoates of light lanthanides(III) were obtained as mono-, di-or trihydrates with metal to ligand ratio
of 1:3 and general formula Ln(C8H6ClO3)3·nH2O, where n=1 for Ln=Ce, Pr, n=2 for Ln=Nd, Sm, Eu, Gd and n=3 for Ln=La. The complexes were characterized by elemental analysis, IR spectra, thermogravimetric studies, X-ray diffraction and
magnetic measurements. The carboxylate group appears to be a symmetrical bidentate, chelating ligand. All complexes seem polycrystalline
compounds. Their thermal stabilities were determined in air. When heated they dehydrate to form anhydrous salts which next
are decomposed to the oxides of the respective metals. The solubilities of light lanthanide(III) 4-chloro-2-methoxybenzoates
in water at 293 K are of the order of 10−5 mol dm−3. The magnetic moments were determined over the range of 77–300 K. They obey the Curie-Weiss law. The values of μeff calculated for all compounds are close to those obtained for Ln3+ by Hund and Van Vleck. The results indicate that there is no influence of the ligand field of 4f electrons on lanthanide ions and the metal ligand bonding is mainly electrostatic in nature. 相似文献
15.
Agnieszka Jab?ońska–Wawrzycka Ma?gorzata Zienkiewicz Maciej Hodorowicz Patrycja Rogala Barbara Barszcz 《Journal of Thermal Analysis and Calorimetry》2012,110(3):1367-1376
In this study, we analyzed influence of the type of the syntheses used: hydrothermal and non-hydrothermal on pyridine-2,3-dicarboxylic acid (2,3pydcH2) coordination fashion. Two manganese(II) complexes: [Mn(H2O)3(2,3pydc)] n (1) and [Mn(H2O)6][Mn(2,3pydcH)3]2 (2) were successfully synthesized from the non-hydrothermal reaction system containing organic ligand and different Mn(II) salts. The received complexes have been prepared and characterized by spectroscopic (IR, Raman), structural (X-ray single crystal), and thermogravimetric methods. The results of the crystal study give some evidence that ligand exhibits various topological structures and interesting properties. Pyridine-2,3-dicarboxylic acid acts as monodicarboxylate N,O-chelating anion (complex 2) or a doubly deprotonated three-dentate-N,O,O?? dicarboxylate ion (complex 1). In the [Mn(H2O)6][Mn(2,3pydcH)3]2 the coordination geometry around Mn(1) ion can be considered as being distorted octahedron {MnN3O3}. The Mn(2) cation possesses the same coordination polyhedron (octahedral). We have also analyzed influence of furnace atmosphere on the thermal behavior and the kind of final product. The sample of (1) decomposes in four stages in N2 (368?C1073?K) and the final residue is MnO2. The thermogram of (2) exhibits three main distinct decomposition steps (383?C973?K). A residue of MnO is remained. In both air and nitrogen atmosphere, Mn(II) complexes (1) and (2) keep unchanged over all steps of decomposition. Only the final residues are different (Mn2O3 are formed). The course of pyrolysis and molecular structure of the complexes lead to the same conclusion about the strength of metal?Cligand bonds. On the basis of the above results, it is concluded that the thermal stability of the manganese(II) compounds is slightly different. 相似文献
16.
The gold(I) complexes of imidazolidine-2-thione and its derivatives were synthesized and their 13C NMR and IR spectroscopic studies were carried out. When gold(III) was reacted with the ligands using a 1:4 metal to ligand ratio, gold(III) was reduced to gold(I), the bis complexes of the general formula AuLnX (where n = 2) were formed. However, when gold(III) was reduced to gold(I) by a reducing agent followed by an addition of the ligand to an aqueous or methanolic solution of gold(I), only mono complexes of the type AuLX were obtained. The structures of the reported complexes are proposed on the basis of their spectroscopic measurements. 相似文献
17.
Complexes of yttrium(III) and lanthanides(III) with 4-hydroxy-3,5-dimethoxybenzoic (syringic) acid were obtained as solids
with metal to ligand mole ratio of 1: 3. The compounds were characterized by elemental analysis, IR spectroscopy, X-ray diffraction
patterns, solubility, and thermal studies. The complexes are sparingly soluble in water and stable at room temperature. Compounds
of light lanthanides (from La to Nd) are hydrated and they crystallize in a triclinic system. When heated, they lose water
molecules in one step and in the next step they decompose to oxides. Complexes of yttrium and other lanthanides are anhydrous
and crystallize in a monoclinic system. They are stable up to 300°C and then decompose to oxides. As the coordination number
of lanthanide ions is usually equal to 9 or 8, one can suppose that hydroxy or methoxy groups take part in the coordination
of these metal ions. 相似文献
18.
Two cobalt(II) and cadmium(II) complexes, [Co(H2DMOPhIDC)2(H2O)2] ? 2H2O (H3DMOPhIDC = 2-(3,4-dimethoxyphenyl)-1H-imidazole-4,5-dicarboxylic acid) (I), [Cd(H2MOPhIDC)2-(Phen)] ? C2H5OH (H3MOPhIDC = 2-(3-dimethoxyphenyl)-1H-imidazole-4,5-dicarboxylic acid, Phen = 1,10-phenanthroline) (II), have been hydro(solvo)thermally synthesized by employing two kinds of organic ligands, H3DMOPhIDC or H3MOPhIDC, respectively. The molecular structures of I and II have been characterized by IR spectra, elemental analyses and single-crystal X-ray diffraction (CIF files CCDC nos. 935845 (I), 935846 (II)). Both complexes show three-dimensional supramolecular structures supported by intermolecular H-bonds. Furthermore, the thermogravimetric and photoluminescent properties of two complexes have been investigated as well. 相似文献
19.
M. S. Gruzdev U. V. Chervonova A. M. Kolker A. S. Golubeva 《Journal of Structural Chemistry》2012,53(5):845-850
Mono- and bis-chelate iron(III)-containing complexes with a tridentate azomethine ligand based on n-dodecyloxybenzoic acid ester derivatives with oxybenzoyl-4-salidene-N??-ethyl-N-ethylenediamine with NO 3 ? counterions are obtained. The structure of the compounds is determined by IR spectroscopy, elemental analysis, and mass spectrometry (MALDI-ToF MS). It is found that the complexation of iron salts with tridentate ligands in a mixture of solvents (alcohol:benzene) results in the formation of bischelate compounds of the composition 1:2 with octahedral packing of iron in the complex, while in pure alcohol solutions, asymmetric mono-chelate complexes are obtained. 相似文献
20.
Renata Łyszczek 《Journal of Thermal Analysis and Calorimetry》2008,93(3):833-838
By diffusion in gel medium new complexes of formulae: Nd(btc)⋅6H2O, Gd(btc)⋅4.5H2O and Er(btc)·5H2O (where btc=(C6H3(COO)3
3−) were obtained. Isomorphous compounds were crystallized in the form of globules. During heating in air atmosphere they lose
stepwise water molecules and then anhydrous complexes decompose to oxides.
Hydrothermally synthesized polycrystalline lanthanide trimellitates form two groups of isomorphous compounds. The light lanthanides
form very stable compounds of the formula Ln(btc)⋅nH2O (where Ln=Ce−Gd and n=0 for Ce; n=1 for Gd; n=1.5 for La, Pr, Nd; n=2 for Eu, Sm). They dehydrate above 250°C and then immediately decomposition process occurs. Heavy lanthanides form complexes
of formula Ln(btc)⋅nH2O (Ln=Dy−Lu). For mostly complexes, dehydration occurs in one step forming stable in wide range temperature compounds. As the final
products of thermal decomposition lanthanide oxides are formed. 相似文献