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1.
Brzyska W. Tarnawska A. Twardowska A. Wiśniewska E 《Journal of Thermal Analysis and Calorimetry》2002,68(1):123-129
Y(III) and lanthanide(III) mesaconates were prepared as crystalline solids with general formula Ln2(C5H4O4)3⋅nH2O, where n=7 for La−Pr, n=4 for Y,Nd−Ho, n=8 for Er−Lu. IR spectra of the prepared mesaconates suggest that carboxylate groups are bidentate bridging anf chelating.
During heating the hydrated complexes are dehydrated in one (Y, Nd−Lu) or two steps (La−Pr) and then decompose directly to
oxides (Y, Ce, Pr, Sm, Gd−Lu) or with intermediate formation Ln2O2CO3 (La, Nd, Eu).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
2.
W. Brzyska 《Journal of Thermal Analysis and Calorimetry》2000,59(3):799-806
The rare earth element 2,4,6-trimethylbenzoates were prepared as solids with the general formula Ln(C10 H11 O2 )3 ×n H2 O, where n =2 for Ln =Y, La–Nd, and n =1 for Ln =Sm–Lu. The IR spectra of the complexes prepared were recorded and their solubilities in water and thermal decomposition
in the air were investigated. During heating the hydrated complexes lose all the crystallization water molecules in one (Y,
Ce–Lu) or two steps (La) and then the anhydrous complexes decompose either directly to oxides (Y, Ce, Pr, Sm–Lu) or with intermediate
formation oxocarbonates Ln2 O2 CO3 (La, Nd). The carboxylate groups in the complexes prepared act probably as mono- and bidentate.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Deng Hong Cai Yue‐Peng Chao Hui Chen Chun‐Long Jiang Cai‐Wu Ji Liang‐Nian Chen Chao‐Qiu 《中国化学》2003,21(4):409-414
Three new lanthanide phenoxyacetate complexes with 1,10‐phenanthroline. [Nd(POA)3 (phen)]2 · 2C2H5OH (1), [Eu(POA)3‐ (phen)]2 · 2C2H5OH (2) and [Sm(POA)2(DMSO)(phen)]2‐ (ClO4)2 (3) (POA= phenoxyacetate, phen = 1,10‐phenanthroline, DMSO = dimethyl sulfoxide), were synthesized and characterized by elemental analyses, IR, UV‐vis and FAB‐MS spectra. Their structures were determined by single crystal X‐ray diffraction analysis. In complexes 1 and 2, the carboxylate groups are bonded to Ln3+ ion in three modes: the chelating bidentate, the bridging bidentate and the bridging tridentate. In complex 3, the carboxylate groups are bonded to Sm3+ ion only involved in one mode: the bridging bidentate. The luminescence behavior of complex 2 was also studied by means of emission spectra. 相似文献
4.
Two series of complexes of meconic acid (H3
Mec) with rare-earths have been prepared by varying the preparative procedure. The compounds have the general formulae, [Ln(Mec) (H2O)2]·3 H2O (whereLn=La, Ce, Pr, Nd, Sm, Ho and Y) and [Ln(HMec) (H2
Mec) (H2O)2]·4 H2O (whereLn=La, Pr, Nd and Sm). The infrared spectral data indicate that the carboxylate groups are bound to the rare-earth metal in a bidentate fashion. Thermal studies indicate that two water molecules are coordinated in each case. The complexes are probably polymeric.
Komplexe von Seltenerd-Metallen mit Meconsäure
Zusammenfassung Es wurden zwei Reihen von Komplexen der Meconsäure (H3 Mec) mit Seltenerd-Metallen mit den allgemeinen Formeln [Ln(Mec)(H2O)2]·3 H2O (Ln=La, Ce, Pr, Nd, Sm, Ho, Y) und [Ln(HMec)2(H2 Mec) (H2O)2]·4 H2O (Ln=La, Pr, Nd, Sm) hergestellt. Die IR-Spektren zeigen, daß die Carboxylat-Gruppen in zweizähniger Weise mit den Metallionen koordinieren; thermische Untersuchungen ergeben, daß in beiden Reihen jeweils zwei Wassermoleküle zusätzlich koordiniert sind. Die Komplexe weisen wahrscheinlich eine Polymerstruktur auf.相似文献
5.
Brzyska W. Bartyzel A. Zieniewicz K. Zwolińska A. 《Journal of Thermal Analysis and Calorimetry》2000,63(2):493-500
Rare earth element 3-methyladipates were prepared as crystalline solids with general formula Ln2(C7H10O4)3⋅nH2O, where n=6 for La, n=4 for Ce,Sm–Lu, n=5 for Pr, Nd and n=5.5 for Y. Their solubilities in water at 293 K were determined (2⋅10–3–1.5⋅10–4 mol dm–3). The IR spectra of the prepared complexes suggest that the carboxylate groups are bidentate chelating. During heating the
hydrated 3-methyladipates lose all crystallization water molecules in one (Ce–Lu) or two steps (Y) (except of La(III) complex
which undergoes tomonohydrate) and then decompose directly to oxides (Y, Ce) or with intermediate formation of oxocarbonates
Ln2O2CO3 (Pr–Tb) or Ln2O(CO3)2 (Gd–Lu). Only La(III) complex decomposes in four steps forming additionally unstable La2(C7H10O4)(CO3)2.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
Gaël Zucchi Dr. Olivier Maury Dr. Pierre Thuéry Dr. Frédéric Gumy Jean‐Claude G. Bünzli Prof. Dr. Michel Ephritikhine Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(38):9686-9696
Treatment of Ln(NO3)3?nH2O with 1 or 2 equiv 2,2′‐bipyrimidine (BPM) in dry THF readily afforded the monometallic complexes [Ln(NO3)3(bpm)2] (Ln=Eu, Gd, Dy, Tm) or [Ln(NO3)3(bpm)2]?THF (Ln=Eu, Tb, Er, Yb) after recrystallization from MeOH or THF, respectively. Reactions with nitrate salts of the larger lanthanide ions (Ln=Ce, Nd, Sm) yielded one of two distinct monometallic complexes, depending on the recrystallization solvent: [Ln(NO3)3(bpm)2]?THF (Ln=Nd, Sm) from THF, or [Ln(NO3)3(bpm)(MeOH)2]?MeOH (Ln=Ce, Nd, Sm) from MeOH. Treatment of UO2(NO3)2?6H2O with 1 equiv BPM in THF afforded the monoadduct [UO2(NO3)2(bpm)] after recrystallization from MeOH. The complexes were characterized by their crystal structure. Solid‐state luminescence measurements on these monometallic complexes showed that BPM is an efficient sensitizer of the luminescence of both the lanthanide and the uranyl ions emitting visible light, as well as of the YbIII ion emitting in the near‐IR. For Tb, Dy, Eu, and Yb complexes, energy transfer was quite efficient, resulting in quantum yields of 80.0, 5.1, 70.0, and 0.8 %, respectively. All these complexes in the solid state were stable in air. 相似文献
7.
Two new neodymium complexes, [Nd2(abglyH)6(2,2′-bipy)2(H2O)2] · 4H2O 1 and {[Nd(abglyH)3(H2O)2] · (4,4′-bipy) · 7H2O}n
2 (abglyH2 = N-P-acetamidobenzenesulfonyl-glycine acid, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), have been synthesized and
their structures have been measured by X-ray crystallography. In 1, nine-coordinated Nd(III) ions are bridged by two syn–syn bidentate and two tridentate bridging carboxylate groups from four different abglyH− anions to form dinuclear motifs, which are further connected into a 3-D supramolecular framework via hydrogen bonds between
the binuclear motifs and the uncoordinated water molecules. In 2, eight-coordinated Nd(III) ions are linked by six carboxylate groups adopting a syn–syn bidentate bridging fashion to form a 1-D inorganic–organic alternating linear chain. These polymeric chains generate microchannels
extending along the a direction, and these cavities are occupied by discrete tetradecameric water clusters, which interact with their surroundings
and finally furnish the 3-D supramolecular network via hydrogen bonds. At the same time, π–π stacking interactions between
benzene rings from abglyH− anions also play an important role in stabilizing the network. 相似文献
8.
Recrystallization of Ln(NO3)3 (Ln = Sm, Eu, Yb) in the presence of 18‐crown‐6 under aqueous conditions yielded [Ln(NO3)3(H2O)3] · 18‐crown‐6. X‐ray crystallography revealed isomorphous structures for each of the lanthanide complexes where [Ln(NO3)3(H2O)3] is involved in hydrogen bonding interactions with 18‐crown‐6. The transition point where the structural motif changes from [Ln(18‐crown‐6)(NO3)3] (with the metal residing in the crown cavity) to [Ln(NO3)3(H2O)3] · 18‐crown‐6 has been identified as at the Nd/Sm interface. A similar investigation involving [Ln(tos)3(H2O)6] (tos = p‐toluenesulfonate) and 18‐crown‐6 were resistant to crown incorporation. X‐ray studies show extensive intra‐ and intermolecular hydrogen bonding is present. 相似文献
9.
G. G. Skvortsov M. V. Yakovenko G. K. Fukin E. V. Baranov Yu. A. Kurskii A. A. Trifonov 《Russian Chemical Bulletin》2007,56(3):456-460
The reactions of lanthanide tris(borohydrides) Ln(BH4)3(thf)3 (Ln = Sm or Nd) with 2 equiv. of lithium N,N′-diisopropyl-N′-bis(trimethylsilyl)guanidinate in toluene produced the [(Me3Si)2NC(NPri)2]Ln(BH4)2Li(thf)2 complexes (Ln = Sm or Nd), which were isolated in 57 and 42% yields, respectively, by recrystallization from hexane. X-ray
diffraction experiments and NMR and IR spectroscopic studies demonstrated that the reactions afford monomeric ate complexes, in which the lanthanide and lithium atoms are linked to each other by two bridging borohydride groups. The complexes
exhibit catalytic activity in polymerization of methyl methacrylate.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 441–445, March, 2007. 相似文献
10.
Monica-Cornelia Sardaru Narcisa Laura Marangoci Sergiu Shova Dana Bejan 《Molecules (Basel, Switzerland)》2021,26(22)
A series of neutral mononuclear lanthanide complexes [Ln(HL)2(NO3)3] (Ln = La, Ce, Nd, Eu, Gd, Dy, Ho) with rigid bidentate ligand, HL (4′-(1H-imidazol-1-yl)biphenyl-4-carboxylic acid) were synthesized under solvothermal conditions. The coordination compounds have been characterized by infrared spectroscopy, thermogravimetry, powder X-ray diffraction and elemental analysis. According to X-ray diffraction, all the complexes are a series of isostructural compounds crystallized in the P2/n monoclinic space group. Additionally, solid-state luminescence measurements of all complexes show that [Eu(HL)2(NO3)3] complex displays the characteristic emission peaks of Eu(III) ion at 593, 597, 615, and 651 nm. 相似文献
11.
Conditions for the formation of rare earth element (Y, La–Lu) 3-methylglutarates were studied and their quantitative composition
and solubilities in water at 293 K were determined (10–2 mol dm–3). The IR spectra of the prepared complexes with general formula Ln2(C6H8O4)3
nH2O (n=3–8) were recorded and their thermal decomposition in the air were investigated. During heating the hydrated 3-methylglutarates
are dehydrated in one step and next anhydrous complexes decompose to oxides Ln2O3 with intermediate formation Ln2O2CO3 (Y, La, Nd–Gd) or directly to the oxides, Ln2O3, CeO2, Pr6O11 and Tb4O7 (Ce, Pr, Tb–Lu).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
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
13.
Summary Complexes of heavy lanthanide(III) (Gd-Lu) and Y(III) with 4-chlorophthalic acid were prepared and their IR spectra, solubility
in water at 295 K and thermal decomposition were investigated. When heated the complexes with general formula Ln2[ClC6H3(CO2)2]3·nH2O where n=6 for Tb, Dy(III), n=4 for Gd, Ho and Er(III), n=2 for Tm-Lu(III) and n=3 for Y(III) decompose to the oxides Ln2O3, Tb4O7 with intermediate formation of oxochlorides LnOCl. 相似文献
14.
A. Kula 《Journal of Thermal Analysis and Calorimetry》2002,68(3):957-964
Complexes of lanthanide(III) (La–Lu) and Y(III) with 1-hydroxy-2-naphthoic acid were obtained as crystalline compounds with
a general formula Ln[C10H6(OH)COO]3⋅nH2O:n=6 for La–Tm and Y, n=2 for Yb and n=0 for Lu. IR spectra of the prepared complexes were recorded, and their thermal decomposition in air were investigated. Spectroscopic
data suggest that in the coordination of metal-organic ligand only oxygen atoms from the carboxylate group take part. When
heated, the complexes decompose to the oxides Ln2O3, CeO2, Pr6O11 and Tb4O7 with intermediate formation of Ln(C11H7O3)(C11H6O3).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Rare earth picrate complexes
with L-leucine (Leu) were synthesized and
characterized. Elemental analysis (CHN), EDTA titrations and thermogravimetric
data suggest a general formula RE(pic)32Leu⋅5H2O
(RE=La–Lu, Y and pic=picrate).
IR spectra indicate the presence of water and suggest that L-leucine is coordinated
to the central ion through the nitrogen of the aminogroup. The absorption
spectrum of the solid Nd compound indicates that the metal-ligand bonds show
a weak covalent character. Emission spectra and biexponential behavior of
the luminescence decay of the Eu compound suggest the existence of polymeric
species. Thermal analysis results indicate that all the compounds present
a similar behavior, with five major thermal decomposition steps. The final
products are rare earth oxides. A slow heating rate is necessary to observe
all decomposition steps. 相似文献
16.
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
17.
18.
Twenty new complexes of chlorides and bromides of yttrium and lanthanides with the Schiff base 4-N-(4′-antipyrylmethylidene)aminoantipyrine
(AA) have been prepared and characterised. They have the general formula, [Ln(AA)2Cl3] and [Ln(AA)2Br2]Br where Ln = Y, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho and Er. Molar conductance studies indicate slight dissociation for the chloride
complexes and 1:1 electrolytic behaviour for the bromide complexes. The magnetic moments of all the complexes agree well with
Van Vleck values. The infrared spectra reveal that AA functions as a terdentate ligand in all these complexes coordinating
through the oxygens of both the carbonyl groups and the azomethine nitrogen. Electronic spectra of Nd, Ho and Er for the chloride
complexes and that of Pr, Nd, Ho and Er for the bromide complexes show weak covalency in the metal-ligand bond. 相似文献
19.
Kalagouda B. Gudasi Rashmi V. Shenoy Ramesh S. Vadavi Manjula S. Patil Siddappa A. Patil 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(1-2):93-101
Reaction of Ln(NO3)3 with 2,6-bis[(3-methoxysalicylidene)hydrazino carbonyl]pyridine (BMSPD) afforded binuclear complexes of the type [Ln2(BMSPD)(NO3)2(H2O)5]·3H2O in case of La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III) and Dy(III), and [Ln2(BMSPD)(NO3)2(H2O)5] in case of Y(III). The mode of coordination of ligand and the conformational changes on complexation with lanthanides was studied based on elemental analysis, magnetic studies, TG/DTA, IR, 1H-NMR, Electronic, EPR and Fluorescence spectral studies. The ligand coordinates to one metal centre through enolized deprotonated carbonyls and pyridine nitrogen whereas doubly deprotonated phenolate oxygens and two hydrazonic nitrogens ligate to another lanthanide centre. Both the metal ions are in eight-coordination environments. The ligand and complexes were further tested for antifungal and antibacterial activities. 相似文献
20.
The complexes Ln(NO3)3(OPCy3)3(EtOH)x (Cy = cyclohexyl, C6H11x = 0 for Ln = Eu, Er, x = 0.5 for Ln = La, Nd and x = 1 for Ln = Tm, Yb) have been prepared by reaction of lanthanide nitrates with Cy3PO in ethanol. The single crystal X-ray structures for Ln = La, Nd, Eu, Er, Tm and Yb are reported. The structures for Ln = La–Eu have two molecules in the unit cell in which the nitrates are all bound as bidentate ligands. The unit cell for Ln = Er contains two distinct molecules; one with three bidentate nitrates and one with two bidentate and one monodentate nitrate. The Tm and Yb complexes have one molecule in the unit cell with two bidentate and one monodentate nitrate ligands. The monodentate nitrates are hydrogen bonded to ethanol in the Tm and Yb structures but not in the Er complex. The infrared spectra of the three classes of complex do not readily permit identification of the monodentate nitrate groups. Electrospray mass spectrometry indicates that redistribution/ionisation reactions occur in solution. Ions formed by solvolysis reactions are attributed to gas phase processes associated with the electrospray technique. Tandem mass spectrometry for the La, Ho and Yb complexes shows that in the gas phase loss of Cy3PO is the sole fragmentation pathway for all but the Yb complex where the higher energy required for initial fragmentation leads to a more complex fragmentation pattern. 相似文献