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1.
The aluminium(III)–citrate complex (NH4)4[Al2(C6H4O7)(C6H5O7)2]·4H2O was characterized using anion exchange chromatography on-line coupled with the element specific ICP-AES detector. Time-dependent monitoring of individual species in aqueous solution at different temperatures gave information about the species stability and the decomposition pathway. The aluminium–citrate complex (NH4)4[Al2(C6H4O7)(C6H5O7)2]·4H2O disintegrated via an unknown intermediary Al(III)–citrate species from which the thermodynamically stable complex [Al3(C6H4O7)3(OH)(H2O)]4− was formed. The activation energy for the decomposition reaction and the pre-exponential factor were determinated to be Ea = 81.95 kJ mol−1 and A = 3.62 × 1013 s−1.  相似文献   

2.
Thirteen phases are now evidenced in the composition space diagram of the Al(OH)3tren–HF–ethanol system at 190 °C. Solvothermal syntheses are performed under microwave heating. Six new organic–inorganic fluorides crystallise and their structures are determined: (H3O)·[H4tren]2·(AlF6)3·6H2O (P-1, Z = 2), [H3tren]2·(AlF5(H2O))3·8H2O (C2/c, Z = 8), [H3tren]4·(AlF6)2·(Al2F11)·(F)·10H2O (P21/n, Z = 2), [H3tren]2·(Al4F18)·3.5H2O (P63, Z = 2), [H3tren]2·(Al4F18) (P-1, Z = 1), and [H3tren]4·(Al8F35)·(OH)·H2O (P-1, Z = 1). The existence domains are approximately located for all phases. Tren amine is tetraprotonated at high HF concentration, otherwise it is triprotonated. A protonated water cluster, H3O+(H2O)6, appears in (H3O)·[H4tren]2·(AlF6)3·6H2O while a new Al4F18 unit, found in [H3tren]2·(Al4F18), is evidenced; it results from corner and edge sharing association of four AlF6 octahedra. Finally, the structure of [H3tren]4·(Al8F35)·(OH)·H2O revealed the largest known fluoroaluminate polyanion, built from eight vertex sharing AlF6 octahedra, (Al8F35)11−.  相似文献   

3.
New polymeric yttrium-succinates, Y2(C4H4O4)3(H2O)4·6H2O and Y2(C4H4O4)3(H2O)2, have been synthesized, and their structures (solved by single crystal XRD) are compared with that of Y2(C4H4O4)3(H2O)2·H2O. Three compounds were obtained as single phases, and their thermal behaviour is described.  相似文献   

4.
Four coordination compounds, namely [Na(H2O)(H2O)2⊂C40H50N20O10](C6H6O2)2Cl·8H2O (1), [K2(H2O)2(H2O)⊂C40H50N20O10](C6H6O2)2Cl2·7H2O (2), [Rb2(H2O)2(H2O)⊂C40H50N20O10](C6H6O2)2Cl2·7H2O (3) and [Cs(H2O)2(H2O⊂C40H50N20O10)](C6H6O2)2Cl·6H2O (4), were obtained by the reactions of the corresponding alkali metal salts with decamethylcucurbit[5]uril (Me10Q[5]) in the presence of hydroquinone, and their structures were determined by single-crystal X-ray diffraction. The results revealed that in compounds 1 and 4 each Me10Q[5] ligand coordinates one Na+ or Cs+ ion to form a molecular bowl structure, while in compounds 2 and 3 each Me10Q[5] ligand coordinates two K+ or Rb+ ions to form a closed molecular capsule structure, and adjacent molecular capsules bridge each other through water molecules to form 1D coordination polymers. In addition, we found that the coordination distances for the metal ions and the height of the metal ions out-of-portal-plane for the four compounds are in the same order, 1 < 2 < 3 < 4, which is attributed to the fact that the radius of alkali cations is in the order Na+ < K+ < Rb+ < Cs+. Although each portal of Q[6] binds with two alkali cations (not including Cs+), the Q[6]-based alkali cations complexes display similar structural trends.  相似文献   

5.
Compounds of the composition La(bpyO2 *)4Cl3·4H2O, La(bpyO2)3Cl3·5H2O, La(bpyO2)2Cl3·3H2O, La(bpyO2)Cl3·3H2O, La(bpyO2)4Br3·4H2O, La(bpyO2)3Br3·8H2O, La(bpyO2)2Br3·7H2O, La(bpyO2)Br3·4H2O, La(bpyO2)4I3·3H2O, La(bpyO2)3(NO3)3·2H2O, La(bpyO2)2(NO3)3·2H2O, La(bpyO2)4(SCN)3·3H2O, La(bpyO2)3(SCN)3·2H2O, La(bpyO2)2(SCN)3·2H2O were isolated. They were investigated by means of thermoanalysis, I.R. spectroscopy, X-ray diffraction and molar conductivity.  相似文献   

6.
Zusammenfassung Systematisch wurden, teils durch Eindampfen von Lösungen, teils durch fraktionierte Ausfällung mittels Alkanolen, Stoffe mit verschiedenen molaren Verhältnissen an Aluminium-, Tartratund kompensierenden Natrium- bzw. Sulfationen hergestellt. Das Verhalten bei der Herstellung, die chemischen Eigenschaften, die Röntgendiagramme, die Gewichts- und Differentialthermoanalyse17 sowie die Infrarot-Spektroskopie23 zeigten, daß folgende Stoffe als chemische Individuen anzusehen sind (T 4- ist das vierbasische Anion der Weinsäure C4H2O 4–):Al2H2 T(SO4)2·6 H2O, Al2HT(SO4)1,5·6 H2O, Al2 TSO4·6 H2O, Al4 T 3·12 H2O, NaAlT·3 H2O, AlH3 TSO4·3 H2O, AlH2 T(SO4)0,5·3 H2O, AlHT·3 H2O, Na2AlTOH·2 H2O, Na3AlT(OH)2·2 H2O, NaAlH4 T 2·3 H2O, Na2AlH3 T 2·4 H2O, Na3AlH2 T 2·4 H2O, Na4AlHT 2·5 H2O, Na5AlT 2·4 H2O.
A systematic preparation of compounds, containing varying molar ratios of aluminum, sodium, tartrate and sulfate was undertaken. The compounds were precipitated either by concentrating the corresponding solutions, or by fractional precipitation with alcohols. The chemical identity of the 15 compounds was confirmed by their chemical properties, X-ray diffraction, gravimetric analysis, and differential thermoanalysis as well as I.R. spectroscopy.
  相似文献   

7.
用热分析与气相色谱联用技术(TA-GC)研究KHC2O4·H2O的热分解表明,在空气和氦气当中,开始时缓慢分解,放出结晶水。接着KHC2O4快速分解成K2C2O4,并释放出一些气体产物:O2(分解初期)、CO、CO2和H2O。讨论了KHC2O4的分解机理。  相似文献   

8.
The reactions of the [Mo33-Q)(μ2-Q)3(H2O)3(C2O4)3]2− complex (Q = S or Se) with CuX salts (X = Cl, Br, I, or SCN) in water produce the cuboidal heterometallic clusters [Mo3(CuX)(μ3-Q)4(H2O)3(C2O4)3]2−, which were isolated as the potassium and tetraphenylphosphonium salts. Two new compounds, K2[Mo3(CuI)(μ3-S)4(H2O)3(C2O4)3]·6H2O and (PPh4)2[Mo3(CuBr)(μ3-S)4(H2O)3(C2O4)3]·7H2O, were structurally characterized. All compounds were characterized by elemental analysis and IR spectroscopy. The K2[Mo3(CuI)(μ3-Se)4(H2O)3(C2O4)3] compound was characterized by the 77Se NMR spectrum; the (PPh4)2[Mo3(CuI)(μ3-S)4(H2O)3(C2O4)3], (PPh4)2[Mo3(CuI)(μ3-Se)4(H2O)3(C2O4)3] and K2[Mo3(CuSCN)(μ3-S)4(H2O)3(C2O4)3]·7H2O compounds, by electrospray mass spectra. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1639–1644, September, 2007.  相似文献   

9.
Thermal decomposition of Pu(C2O4)2·6H2O, Pu2(C2O4)3·10H2O and Np(C2O4)2 ·6H2O has been studied by using combination of gas chromatography, infrared spectroscopy, spectrophotometry and complex thermal analysis. We also investigated the decomposition of Pu oxalate under its -radiation. The reduction of Pu(IV) to Pu(III) has been confirmed. We found Np(V), which is formed from Np(IV), on the basis of infrared and absorption spectra of the intermediate compounds.  相似文献   

10.
Summary Compounds crystallizing from theMOH-HF-V2O5-H2O2-H2O (M=N(CH3)4, N(C2H5)4, N(C4H9)4) system have been characterized by elemental analysis, vibrational spectra, and X-ray powder patterns. Besides [N(CH3)4]2[VO(O2)2F]·2H2O (1) and [N(CH3)4]3[V2O2(O2)4F] (2) which correspond to the known compoundsM 2[VO(O2)2F] (M=K, NH4, Cs) and (NH4)3[V2O2(O2)4F]·2H2O, respectively, complexes of two new types have been obtained: [N(C2H5)4]2[V2O5–x (O2) x F2]·H2O(x0.25,3) and the first trinuclear peroxo complex of vanadium(V), [N(C4H9)4]2[V3O3(O2)4F3]·6H2O(4).
Tetraalkylammonium-Fluorooxoperoxovanadate
Zusammenfassung Aus dem SystemMOH-HF-V2O5-H2O2-H2O (M=N(CH3)4), N(C2H5)4, N(C4H9)4) kristallisierende Verbindungen wurden mittels Elementaranalyse, Schwingungsspektroskopie und Röntgendiffraktion charakterisiert. Neben [N(CH3)4]2[VO(O2)2F]·2H2O (1) und [N(CH3)4]3][V2O2(O2)4F] (2), welche den bekannten VerbindungenM 2[VO(O2)2F] (M=K, NH4, Cs) und (NH4)3[V2O2(O2)4)F]·2H2O entsprechen, wurden zwei neue Typen von Komplexen erhalten: [N(C2H5)4]2[V2O5–x (O2) x F2]·H2O (x0.25,3) und der erste dreikernige Peroxokomplex von Vanadium(V), [N(C4H9)4]2[V3O3(O2)4F3]·6H2O (4).
  相似文献   

11.
Six domains appear in the 2D composition diagram of the Al(OH)3-dien-HFaq.-ethanol system at 190 °C and [Al3+] = 1 mol L−1 under microwave heating. Four organic-inorganic fluorides crystallise: [H3dien]·(AlF6) (P21/c, Z = 4), [H3dien]2·(AlF5(H2O))3·2H2O (P21/n, Z = 4), [H3dien]·(AlF6)·2H2O, which was previously known, and [H3dien]2·(Al4F18) (C2/c, Z = 4). A new (Al4F18)6− polyanion, which results from the tetrahedral association of four AlF6 octahedra linked by corners, is evidenced in [H3dien]2·(Al4F18).  相似文献   

12.
Samsonenko  D. G.  Sokolov  M. N.  Gerasko  O. A.  Virovets  A. V.  Lipkowski  J.  Fenske  D.  Fedin  V. P. 《Russian Chemical Bulletin》2003,52(10):2132-2139
Slow evaporation of solutions of samarium nitrate and thorium chloride in hydrochloric acid containing the macrocyclic cavitand cucurbituril (C36H36N24O12) afforded crystals of the [{Sm(H2O)5(NO3)}2(C36H36N24O12)](NO3)4·6.5H2O and [{Th(H2O)5Cl}2(C36H36N24O12)]Cl6·13H2O complexes, respectively. The [Sm(C36H36N24O12)(H2O)5(SO4)][Sm(H2O)5(SO4)2]·17H2O complex was generated upon heating (130 °C) of a mixture of samarium sulfate, cucurbituril, and water in a sealed tube. X-ray diffraction analysis demonstrated that the metal atoms in these complexes are bound to the portal oxygen atoms of the cucurbituril molecules. In addition, the portal oxygen atoms of cucurbituril are linked to the coordinated H2O molecules via hydrogen bonds.  相似文献   

13.
The thermal decomposition of K3[OH{VO(O2)2}2]·H2O was studied under dynamic conditions up to 350°C and also isothermally at 150°±3°C in self-generated atmosphere. K4[V2O6(O2)] is formed as the reaction intermediate. The final products of thermal decomposition of K3[OH{VO(O2)2}2]·H2O are KVO3 and K4V2O7.
Zusammenfassung Unter dynamischen Bedingungen bis 350°C und isotherm bei 1503°C in selbsterzeugter Atmosphäre wurde die thermische Zersetzung von K3[OH{VO(O2)2}2]H2O untersucht. Als Zwischenprodukt der Reaktion wird K4[V2O6(O2)] gebildet. Die Endzersetzungsprodukte von K3[OH{VO(O2)2}2]H2O sind KVO3 und K4V2O7.
  相似文献   

14.
Four new [H3tren]3+ or [H4tren]4+ fluoride zirconates and two new [H3tren]3+ fluoride tantalates are evidenced in the (ZrF4 or Ta2O5)-tren-HFaq.-ethanol systems at 190 °C: the structurally related phases [H4tren]·(Zr2F12)·H2O and α-[H4tren]·(Zr2F12) (P212121), β-[H4tren]·(Zr2F12) (P21/c), [H3tren]4·(ZrF8)3·4H2O (I23), β-[H3tren]2·(Ta3O2F16)·(F) (R32) and its monoclinic distortion α-[H3tren]2·(Ta3O2F16)·(F) (C2/m). α and β-[H4tren]·(Zr2F12) and [H4tren]·(Zr2F12)·H2O are built up from (Zr2F12) dimers of edge sharing ZrF7 polyhedra while isolated ZrF8 dodecahedra are found in [H3tren]4·(ZrF8)3·4H2O. Linear (Ta3O2F16) trimers build α and β-[H3tren]2·(Ta3O2F16)·(F); they consist of two (TaOF6) pentagonal bipyramids that are linked to two opposite oxygen atoms of one central (TaO2F4) octahedron. A disorder affects the equatorial fluorine atoms of the trimers and eventually carbon or nitrogen atoms of [H3tren]3+ cations.  相似文献   

15.
The mechanism of formation of zinc ferrite (ZnFe2O4) from ZnC2O4·1.8H2O-2FeIIC2O4·2H2O and ZnC2O4·1.8H2O-Fe2III(C2O4)3·6H2O mixtures is investigated. By combination of TG and XRPD measurements it has been shown that microcrystalline ZnFe2O4 forms from physical mixtures after prolonged annealing at 1000 °C while nanocrystalline ZnFe2O4 powders are produced by mild annealing (1 h at 500 °C in air) of mechanically activated mixtures. The magnetic properties of ZnFe2O4 powders obtained from physical and from milled mixtures are compared.  相似文献   

16.
Tren amine cations [(C2H4NH3)3N]3+ and zirconate or tantalate anions adopt a ternary symmetry in two hydrates, [H3tren]2·(ZrF7)2·9H2O and [H3tren]6·(ZrF7)2·(TaOF6)4·3H2O, which crystallise in R32 space group with aH = 8.871 (2) Å, cH = 38.16 (1) Å and aH = 8.758 (2) Å, cH = 30.112 (9) Å, respectively. Similar [H3tren]2·(MX7)2·H2O (M = Zr, Ta; X = F, O) sheets are found in both structures; they are separated by a water layer (Ow(2)-Ow(3)) in [H3tren]2·(ZrF7)2·9H2O. Dehydration of [H3tren]2·(ZrF7)2·9H2O starts at room temperature and ends at 90 °C to give [H3tren]2·(ZrF7)2·H2O. [H3tren]2·(ZrF7)2·H2O layers remain probably unchanged during this dehydration and the existence of one intermediate [H3tren]2·(ZrF7)2·3H2O hydrate is assumed. Ow(1) molecules are tightly hydrogen bonded with -NH3+ groups and decomposition of [H3tren]2·(ZrF7)2·H2O occurs from 210 °C to 500 °C to give successively [H3tren]2·(ZrF6)·(Zr2F12) (285 °C), an intermediate unknown phase (320 °C) and ZrF4.  相似文献   

17.
Hydrolysis and speciation of aluminium sulfate octadecahydrate Al2(SO4)3·18H2OAl2(SO4)3·18H2O was studied by electrospray time of flight mass spectrometry (ESI TOF MS). Several novel polymeric species were determined. Highly charged polymers, characterized by other methods, such as the Keggin cation [Al13O4(OH)24(H2O)12]7+ and the octameric aluminium hydroxide cluster [Al8(OH)14(H2O)18](SO4)5 16H2O, were found using ESI-MS as the anions [Al13O4(OH)25(SO4)4]2− and [Al8O(OH)14(SO4)5(H2O)4]2−. All the main species identified contained sulfate or hydrogen sulfate. The compositions of the determined ions mimicked those of several stable mineral forms.  相似文献   

18.
The mixed‐metal and mixed‐valance carboxylates of MFe2O(O2CCF3)6(C4H8O)2(H2O) (M = Zn, Mn, Cu) and MFe2O(O2CCCl3)6(C4H8O)2(H2O) (M = Zn, Fe) were utilized as potential precursors for the preparation of spinel. In the pyrolysis of ZnFe2O(O2CCF3)6(C4H8O)2(H2O) in air at 400 °C pure ZnFe2O4 is formed, in contrast to pyrolysis of the trichloro derivative, which resulted in the formation of ZnO and Fe2O3. In the pyrolysis of MnFe2O(O2CCF3)6(C4H8O)2(H2O) in nitrogen, MnFe2O4 was the main phase and single oxides were the minor phases. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

19.
Results are reported for FeC2O4·2H2O and Fe2(C2O4)3·5H2O; various stages in the decomposition are demonstrated. The second compound on decomposition in nitrogen gives rise to finely divided Fe3O4 containing a little free metal. The conditions for this are established.  相似文献   

20.
New water-soluble bimetallic peroxo complexes of niobiumV and/or tantalumV with high-denticity polyaminocarboxylate ligands have been prepared, characterized from the spectroscopic point of view, and used as molecular precursors for Nb-Ta mixed oxides. Four new homobimetallic complexes, (gu)3[Nb2(O2)4(dtpaO3)]·3H2O 1, (gu)3[Ta2(O2)4(dtpaO3)]·5H2O 2, (gu)3[Nb2(O2)4(HtthaO4)]·2H2O 4 and (gu)3[Ta2(O2)4(HtthaO4)]·3H2O 5 and the corresponding heterometallic complexes, (gu)3[NbTa(O2)4(dtpaO3)]·2.5H2O 3 and (gu)3[NbTa(O2)4(HtthaO4)]·2H2O 6 have been obtained. In these compounds, the in situ oxidation of the nitrogen atoms of the PAC ligands into N-oxide groups has been evidenced by IR spectroscopy and mass spectrometry. The thermal treatment of the homonuclear complexes in air at 700 or 800 °C, depending on the Ta content, provided Nb2O5 or Ta2O5 while the heteronuclear compounds led to the solid solution TaNbO5. BET and SEM measurements have been carried out and comparison of the morphology of the samples prepared from homo- and heterometallic precursors is discussed.  相似文献   

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