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1.
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
2.
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
3.
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
4.
The conditions of thermal decomposition of the 3-chlorobenzoates of Y, La and the lanthanides from Ce(III) to Lu have been studied. The complexes of La, Pr(III), Sm, Eu, Gd, Tb(III) and Dy were prepared as heptahydrates, those of Ce(III) and Y as pentahydrates, that of Nd as the tetrahydrate, that of Ho as the dihydrate and those of Er, Tm, Yb and Lu as anhydrous salts. On heating, these complexes decompose in three or two stages. They first lose some water molecules and then decompose to oxides through the intermediate formation of LnOCl. Cerium(III) 3-chlorobenzoate loses its crystallization water in two stages and yields the anhydrous salt, which is then transformed directly into CeO2. All these complexes melt before decomposition in the temperature range 441–513 K. 相似文献
5.
The condition of thermal decomposition of La, Ce(III), Pr(III), Nd, Sm, Eu(III), Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu suberates were studied. The suberates of Ce(III), Sm, Eu(III), Ho, Tm, Yb and Lu heated lose crystallization water. Anhydrous Sm and Eu(III) suberates decompose to oxides with intermediate formation Ln2O2CO3, whereas suberates of other lanthanides decompose directly to oxides. Suberates of La, Pr(III), Nd, Gd, Tb, Dy and Er lose some water molecules and then decompose directly to oxides. Only La complex decomposes to La2O3 via the intermediate formation La2O2CO3.
Zusammenfassung Es wurden die UmstÄnde der thermischen Zersetzung von La-, Ce(III)-, Pr(III)-, Nd-, Sm-, Eu(III)-, Gd-, Tb-, Dy-, Ho-, Er-, Tm-, Yb- und Lu-suberat untersucht. Bei Erhitzen verlieren Ce(III)-, Sm-, Eu(III)-, Ho-, Tm-, Yb- und Lu-suberat Kristallwasser. Wasserfreies Sm-bzw. Eu(III)-suberat zersetzt sich über das Zwischenprodukt der Zusammensetzung Ln2O2CO3 zum Oxid, wÄhrend sich die Suberate der anderen Lanthanoide direkt zu den Oxiden zersetzen. La-, Pr(III)-, Nd-, Gd-, Tb-, Dy- und Er-suberat geben einige Moleküle Kristallwasser ab und zersetzen sich dann direkt zu den Oxiden. Nur der Lanthankomplex zersetzt sich zu La2O3 über das Zwischenprodukt La2O2CO3.相似文献
6.
Thermal and spectral studies of 2,4,5-trimethoxybenzoates of heavy lanthanides(III) and yttrium(III)
W. Ferenc A. Walków-Dziewulska B. Bocian 《Journal of Thermal Analysis and Calorimetry》2005,79(1):145-150
2,4,5-Trimethoxybenzoates of Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), Lu(III) and Y(III) are crystalline, hydrated salts with colours typical for M(III) ions. The carboxylate group is a bidenate, chelating ligand. The complexes of Tb(III), Dy(III) and Ho(III) are dihydrates while those of Er(III), Tm(III), Yb(III), Lu(III) and Y(III) are trihydrates. These compounds are characterized by low symmetry. On heating in air to 1273 K, the 2,4,5-trimethoxybenzoates of heavy lanthanides(III) and yttrium(III) decompose in two steps. At first they dehydrate to form anhydrous salts which next are decomposed to the oxides of the respective metals. The values of the enthalpy of dehydration process were determined. The solubility in water at 293 K for all heavy lanthanides(III) and yttrium(III) are in the orders of 10-3-10-4 mol dm-3. The magnetic moments of the complexes were determined in the temperature range 77-300 K. 相似文献
7.
The conditions of thermal decomposition of Y, La, Ce(III), Pr, Nd, Sm, and Gd aconitates have been studied. On heating, the aconitate of Ce(III) loses crystallization water to yield anhydrous salt, which then is transformed in to oxide CeO2. The aconitates of Y, Pr, Nd, Sm, Eu and Gd decompose in three stages. First, aconitates undergo dehydration to form the anhydrous salts, which next decompose to Ln2O2CO3. In the last one the thermal decomposition of Ln2O2CO3 to Ln2O3 is accompanied by endothermic effect. Dehydration of aconitate of La undergoes in two stages. The anhydrous complex decomposes to La2O2CO3; this subsequently decomposes to La2O3. 相似文献
8.
A. Czylkowska 《Journal of Thermal Analysis and Calorimetry》2012,110(3):1299-1308
Novel mixed-ligand complexes with empirical formula Ln(4-bpy)2(CCl3COO)3·nH2O [where Ln(III)?=?Dy, Ho, Er, Tm, Yb, Lu; 4-bpy?=?4,4??-bipyridine] were prepared and characterized by chemical and elemental analysis, infrared spectroscopy, and conductivity measurements (in methanol, dimethylformamide, and dimethyl sulfoxide). X-ray powder diffraction patterns indicate that the complexes are small crystalline compounds. IR spectra of complexes show that all carboxylate groups and 4-bpy are engaged in coordination of lanthanide ions. The thermal behavior of complexes was studied by means of TG, DTG, DTA techniques in the solid state under nonisothermal conditions in air atmosphere. During heating, the complexes decompose via intermediate products to the oxide Ln2O3. The combined TG?CFTIR technique was employed to study the decomposition pathway of the Ho(III) and Tm(III) complexes in flowing argon atmosphere. 相似文献
9.
The conditions of thermal decomposition of La, Ce(III), Pr(III), Nd, Sm(III), Eu, Gd, Tb(III), Dy, Ho, Er, Tm, Yb and Lu sebacates have been studied. When heated in air atmosphere, the sebacates of La and lanthanides with general formula Ln2(C10H16O4)3·nH2O, wheren=6?24, lose some crystallization water molecules in one or two steps at 323–343 K and are then dehydrated and decomposed simultaneously to the oxides Ln2O3, CeO2, Pr6O11 and Tb4O7. The oxides are formed over the range of temperature 783 K (CeO2)?1073 K (Nd2O3). 相似文献
10.
Synthesis And Characterization Of Complexes Of Rare Earth Elements With 1,1-Cyclobutanedicarboxylic Acid 总被引:1,自引:0,他引:1
The complexes of yttrium and lanthanide with 1,1-cyclobutanedicarboxylic acid of the formula: Ln2(C6H6O4)3⋅nH2O, where n=4 for Y, Pr–Tm, n=5 for Yb,Lu, n=7 for La, Ce have been studied. The solid complexes have colours typical of Ln3+ ions. During heating in air they lose water molecules and then decompose to the oxides, directly (Y, Ce, Tm, Yb) or with
intermediate formation. The thermal decomposition is connected with released water (313–353 K), carbon dioxide, hydrocarbons(538–598
K) and carbon oxide for Ho and Lu. When heated in nitrogen they dehydrate to form anhydrous salt and next decompose to the
mixture of carbon and oxides of respective metals. IR spectra of the prepared complexes suggest that the carboxylate groups
are bidentate chelating.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
11.
M. Dabkowska 《Journal of Thermal Analysis and Calorimetry》1990,36(4):1319-1330
The multi-step dehydration and decomposition of trivalent lanthanum and lanthanide heptanediate polyhydrates were investigated by means of thermal analysis completed with infrared study. Further more, X-ray diffraction data for investigated heptanediate complexes of general stoichiometry Ln2(C7H10O4)3.nH2O (wheren=16 in the case of La, Ce, Pr, Nd and Sm pimelates,n=8 for Eu, Gd, Tb, Dy, Er and Tm pimelates,n=12 for Ho, Yb and Lu pimelates) were also reported.
Zusammenfassung Mittels TG, DTG, DTA wurde in Verbindung mit IR-Methoden der mehrstufige Dehydratations- und der Zersetzungsvorgang der Polyhydrate der PimelinsÄuresalze von dreiwertigem Lanthan und dreiwertigen Lanthanoiden untersucht. Röntgendiffraktionsdaten der untersuchten Heptandiat-Komplexe mit der allgemeinen Formel Ln2(C7H10O4)3 nH2O (mitn=16 für Ln=La, Ce, Pr, Nd und Sm,n=8 für Ln=Eu, Gd, Tb, Dy, Er und Tm sowien=12 für Ln=Ho, Yb und Lu) werden ebenfalls gegeben.相似文献
12.
Z. Rzączyńska M. Woźniak W. Wołodkiewicz A. Ostasz S. Pikus 《Journal of Thermal Analysis and Calorimetry》2007,88(3):871-876
The complexes of yttrium(III) and lanthanides(III) with 5-amino-1,3-benzenedicarboxylic acid form two isostructural series
of compounds and have the general formula Ln2(C8H5O4N)3·nH2O, where n = 13 for Y, La-Er and n=9 for Tm, Yb, Lu. They are insoluble in water and stable at room temperature. On heating in air or inert gas atmosphere they
lose all water molecules in several steps. The anhydrous compounds are stable to about 400°C and next decompose to oxides. 相似文献
13.
Z. Rzączyńska J. Sienkiewicz-Gromiuk H. Głuchowska 《Journal of Thermal Analysis and Calorimetry》2010,101(1):213-219
Rare earth complexes with 2,2′-biphenyldicarboxylic acid (diphenic acid = H2dpa) were obtained as hydrated precipitates of the general formula Ln2(C14H8O4)3∙nH2O, where n = 3 for the of Y(III) and Ce(III)–Er(III) and n = 6 for La(III), Tm(III), Yb(III) and Lu(III) complexes. On heating in air atmosphere complexes lose all water molecules in the
temperature range 30–210 °C in one step and form anhydrous compounds, which are stable up to 315–370 °C. During further heating
they decompose to oxides. The trihydrated compounds are crystalline powders whereas the hexahydrated are amorphous solids.
The trihydrated complexes crystallize in the monoclinic (Pr(III) and Ce(III) complexes) and triclinic (Y(III) and Nd(III)–Er(III)
complexes) crystal systems. 相似文献
14.
Hydrothermal phase equilibria studies have been carried out in the Ln2O3-H2O systems (Ln = La, Pr, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) and the stability fields of the phases Ln(OH)3 LnOOH and Ln2O3-C have been established in the pressure-temperature range of 25000 psi and 900° C. The sequioxides Ln2O3-C are stable only in the last four systems of Er to Lu along with the Ln(OH)3 and LnOOH. The systems from Nd to Ho have only Ln(OH)3 and LnOOH as stable phases and those from La to Pr have only Ln(OH)3 as the stable phase. The unit cell parameters of trihydroxides deviate from the values reported in the literature and this
is attributed to the contamination of CO2 in the starting material. 相似文献
15.
The thermal decompositions of Y, La and lanthanide (from Ce(III) to Lu(III) benzene-1,2-dioxyacetates with general formula Ln2(C10H8O6)3·nH2O were studied. The hydrated complexes first lose water of crystallization in one or two steps to yield anhydrous compounds or hydrates containing coordination water molecules, and then decompose to the oxides Ln2O3, CeO2, Pr6O11 and Tb4O7 with formation of intermediates, carbonates and oxycarbonates (La, Pr-Eu), oxycarbonates (Y, Tb-Lu) or carbonate (Gd) only. Anhydrous cerium(III) benzene-1,2-dioxyacetate decomposes on heating directly to CeO2. 相似文献
16.
Summary Reaction of the rare earth chlorides with pyridinium chloride in tetrahydrofuran (THF) under anhydrous conditions gave nearly insoluble precipitates of the composition (pyH)3
RECl6·THF (RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Y, Er, Tm, Yb, and Lu). They were characterized by chemical analysis and IR spectroscopy; decompositionin vacuo was studied, yielding the hithero unknown complexes (pyH)3
RECl6 (RE=La, Ce, Pr, Sm, Tb, Ho, Y, Tm, and Lu). 相似文献
17.
Nicolas Wartenberg Dr. Olivier Raccurt Prof. Elodie Bourgeat‐Lami Dr. Daniel Imbert Dr. Marinella Mazzanti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(10):3477-3482
The bis‐tetrazolate‐pyridine ligand H2pytz sensitises efficiently the visible and/or near‐IR luminescence emission of ten lanthanide cations (Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb). The LnIII complexes present sizeable quantum yields in both domains with a single excitation source. The wide range of possible colour combinations in water, organic solvents and the solid state makes the complexes very attractive for labelling and encoding. 相似文献
18.
A. N. Turanov V. K. Karandashev V. E. Baulin E. V. Kirillov S. V. Kirillov V. N. Rychkov A. Yu. Tsivadze 《Russian Journal of Inorganic Chemistry》2016,61(10):1335-1338
Interfacial distribution of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y between aqueous solutions of their salts and solutions of functionalized ionic liquid, 1,11-bis(1-methylimidazol-3-yl)-3,6,9-trioxaundecane bis(hexafluorophosphate) has been studied. The stoichiometry of extracted complexes has been determined, the effect of HNO3 concentration in aqueous phase on the efficiency of rare earth elements(III) recovery into organic phase has been considered. 相似文献
19.
G Bannach E Schnitzler O Treu
Filho V H S Utuni M Ionashiro 《Journal of Thermal Analysis and Calorimetry》2006,83(1):233-240
Solid-state
compounds of general formula LnL3⋅nH2O,
where Ln represents heavier lanthanides
and yttrium and L is 2-chlorobenzylidenepyruvate,
have been synthesized. Chemical analysis, simultaneous thermogravimetry-differential
analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry,
elemental analysis and infrared spectroscopy have been employed to characterize
and to study the thermal behaviour of these compounds in dynamic air atmosphere.
On heating these compounds
decompose in four (Gd, Tb, Ho to Lu, Y) or five (Eu, Dy) steps. They lose
the hydration water in the first step and the thermal decomposition of the
anhydrous compounds up to 1200°C occurs with the formation of the respective
oxide, Tb4O7 and Ln2O3
(Ln=Eu, Gd, Dy to Lu and Y) as final residue.
The dehydration enthalpies found for these compounds (Eu, to Lu and Y) were:
65.77, 55.63, 86.89, 121.65, 99.80, 109.59, 131.02, 119.78, 205.46 and 83.11
kJ mol-1, respectively. 相似文献
20.
Z. Rzączyńska A. Ostasz M. Sikorska-Iwan H. Głuchowska E. Olszewska S. Pikus 《Journal of Thermal Analysis and Calorimetry》2006,84(3):575-579
The complexes
of yttrium(III) and lanthanides(III) with 1,2,4,5-benzenetetracarboxylic acid
were prepared as crystalline solids of the general formula Ln4(C10H2O8)3⋅14H2O. They
are insoluble in water. On heating in air or inert gas atmosphere all compounds
lose water molecules; next anhydrous compounds decompose to oxides. The yttrium
complex and heavy lanthanide (from Ho to Lu) ones crystallize in monoclinic
crystal system. The dehydration does not change the crystal structure of the
compounds. 相似文献