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  • 1
    Electronic Resource
    Electronic Resource
    Characterization of a [4Fe-4S]-Ferredoxin Model Based on a Concave Tetradentate Thiol Ligand System (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 23-34 
    Details
    ISSN: 0009-2940
    Keywords: Cavitand ; Electrochemistry ; Iron sulfur cluster ; Metalloprotein model ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: NMR and Mössbauer spectroscopy show that a novel tetrathiol ligand, based on the cavitand diphenylglycoluril, encapsulates a 4Fe-4S cluster and induces asymmetry in it. The cluster gives a weak electrochemical current response in DMF, with a half-wave potential for the 2-/3- reduction vs. Fc+/Fc of -1.7 V. Ba2+ ions are adsorbed, according to X-ray analysis of the SEM image of the electrode, and act as modulator and promoter of the electrochemical response. On the basis of cyclic voltammograms it is proposed that this adsorption creates electroactive sites, changing the type of diffusion controlling the mass transport to the electrode from radial to linear, and that it helps the negatively charged complex, which contains a dipole, to approach the negative electrode in an orientation favourable for electron exchange. This feature makes the complex an important model for ferredoxins, in spite of a difference in redox potential.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300105
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  • 2
    Electronic Resource
    Electronic Resource
    Hydrogen Bonding and Conformational Analysis of Chelate-Stabilized Alkoxopalladium(II) Complexes Derived from Amino Alcohol Ligands (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 35-44 
    Details
    ISSN: 0009-2940
    Keywords: Alkoxopalladium(II) ; Conformational analysis ; Hydrogen bonding ; Two-dimensional and cage structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of palladium acetate with two equivalents of di- and triethanolamines RN(CH2CH2OH)2 in the presence of a base affords the new chelate-stabilized alkoxo Pd(II) complexes [Pd(OCH2CH2N(R)CH2CH2OH)2] [R = Me (1), Et (2), n-Bu (3), benzyl (4) or CH2CH2OH (5)]. These N,O-ligated complexes are isolated in high yield as yellow, crystalline solids and are thermally stable despite the presence of several β-hydrogen atoms in the ligand system. Both complexes possess a square-planar palladium coordination geometry with the two oxygen atoms positioned mutually trans. The most notable difference in the molecular structures is that 1 forms a two dimensional network of intermolecular O-H≡O hydrogen bonds, whereas 5 forms intramolecular O-H⃛O hydrogen bonds, which cage the palladium center. In solution 1-4 exist as a diastereoisomeric mixture (a racemic enantiomeric pair SNSN, RNRN and a mesomeric form RNSN) in a 1:1 molar ratio, and this ratio is independent of temperature in nonalcoholic solvents, When complexes 1-4 are dissolved in protic solvents (e.g. MeOH) the diastereomeric excess is temperature-dependent due to an exchange process between the meso diastereoisomer and the (racemic) enantiomeric pair. Thermodynamic parameters for this process in a mixture of MeOH-toluene have been determined with NMR and show this process to be influenced by the steric nature of the alkyl substituent (R) on nitrogen. A conformational analysis based on 1H-NMR coupling constants within the N,O-chelate ring of complexes 1-4 provides details on the solution structure of the ring in both diastereoisomers.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300106
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  • 3
    Electronic Resource
    Electronic Resource
    Coordination Compounds of Coinage Metals with Vinylidenebis(diphenyl-phosphane) and Its Disulfide and Their Reactivity towards NucleophilesDedicated to Professor P. Royo on the occasion of his 60th birthday. (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1513-1517 
    Details
    ISSN: 0009-2940
    Keywords: Gold ; Silver ; Diphosphane ; Diphosphane Disulfide ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinylidenebis(diphenylphosphane) reacts with gold(I) or gold(III) compounds to give dinuclear {[{Au(C6F5)]2[(PPh2)2C=CH2{] or [Au{PPh2C(=CH2)Ph2P)]2(ClO4)2] or mononuclear complexes ([Au(C6F5)3(PPh2C(=CH2)Ph2P)]}, respectively. The latter reacts with gold(I) or silver(I) compounds to afford dinuclear [[Au(C6F5)3[PPh2C(=CH2)Ph2P}AuX], X=Cl or C6F5) or trinuclear species {[{Au(C6F5)3{PPh2C(=CH2)Ph2P{]2M]ClO4, M=Au or Ag}. No addition of nucleophiles to the C=C double bond is observed in these complexes, which contain the diphosphane acting as bridging or monodentate ligand. (SPPh2)2C=CH2 reacts with AgClO4 to give [Ag{SPPh2C(=CH2)Ph2PS}]2-(ClO4)2or[Ag[PPh2C(=CH2)Ph2P]2]ClO4. The crystal structure of [Au(C6F5)3{PPh2C(=CH2)Ph2P}Au(C6F5)] has been established by X-ray crystallography, and confirms the expected square planar and linear geometry for the Au111 and Au1 centres, respectively.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971301026
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  • 4
    Electronic Resource
    Electronic Resource
    Subsite-Specific Reactions of a Cyclotriveratrylene [4Fe-4S] Cluster Complex (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1151-1157 
    Details
    ISSN: 0009-2940
    Keywords: Iron-sulfur clusters ; S ligands ; Cyclotriveratrylene ; Subsite-specific reactions ; Electrochemistry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ligand exchange reactions are carried out exclusively at the unique iron site of a subsite-differentiated cyclotriveratrylene [4Fe-4S] cluster complex. The effect of a variety of thiolate, phenolate, bidentate, and bridging ligands on the redox potential of the subsite-differentiated [4Fe-4S] cluster complex is studied and compared with the effects of such ligands on an [Fe4S4C14]2- cluster. The redox potential can be modulated within the range of -1.60 to -1.80 V (vs. Fc0/+) by varying the ligand. The introduction of an electron releasing substituent shifts the redox potential to more negative values, whereas an electron withdrawing substituent has the opposite effect. A linear relationship exists between the number of substituted sites and the reduction potential of the cluster.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300819
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  • 5
    Electronic Resource
    Electronic Resource
    Hochmolekulare PerchlorsiloxaneProfessor Manfred Weidenbruch zum 60. Geburtstag gewidmet (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1875-1880 
    Details
    ISSN: 0044-2313
    Keywords: Chlorosiloxanes ; mass-spectrometric investigations ; Si-O-frameworks ; SiO-clusters ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: High-molecular PerchlorosiloxanesThe reaction of SiCl4 and O2 in the gas phase does not lead spontaneously to the thermodynamically favored products SiO2 and Cl2. At temperatures of about 1300 K a lot of intermediates SinOmCl4n-2m can be isolated. Massspectrometric investigations show the formation of chlorosiloxanes with n = 2…65 and m/n = 0,5…1,7 and molar masses up to 7000 D. These compounds - even the high molecular ones - show typical molecular behaviour: they are solulable in unpolar solvents like hexane and can be sublimed congruently. No indications could be found between the structures of Si—O-frameworks in the siloxanes and solid SiO2-modifications.
    Notes: Die Reaktion von SiCl4 mit O2 in der Gasphase verläuft nicht spontan zu den thermodynamisch begünstigten Endprodukten SiO2 und Cl2. Bei Reaktionstemperaturen um 1300 K lassen sich zahlreiche Zwischenstufen SinOmCl4n-2m (Perchlorsiloxane) nachweisen und isolieren. Massenspektrometrische Untersuchungen zeigen die Bildung von Chlorsiloxanen mit n = 2…65 und m/n = 0,5…1,7; es wurden Molmassen bis 7000 D nachgewiesen. Auch die sehr hochmolekularen Chlorsiloxane haben typisch molekulare Eigenschaften: Sie sind löslich in unpolaren Solventien wie Hexan und unzersetzt verdampfbar. Es ergaben sich keine Hinweise darauf, daß die SiO-Gerüste in den gebildeten Siloxanen Ausschnitte aus einer der Strukturen der SiO2-Modifikationen darstellen.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976231209
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  • 6
    Electronic Resource
    Electronic Resource
    Reactions of Hexanuclear Niobium and Tantalum Halide Clusters with Mercury(II) Halides. I. Synthesis and structures of the semiconducting compounds [M6Br12(H2O)6][HgBr4] · 12H2O, M=Nb, Ta (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1247-1254 
    Details
    ISSN: 0044-2313
    Keywords: Cluster compounds ; crystal structures ; magnetic properties ; transport properties ; semiconducting properties ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktionen von Hexanuclearen Niob- und Tantal-Halogenid-Clustern mit Quecksilber(II)-Halogeniden. I. Synthese und Struktur der halbleitenden Verbindungen [M6Br12(H2O)6][HgBr4] · 12H2O, M=Nb, TaDie Darstellung der neuen Clusterverbindungen [M6Br12(H2O)6][HgBr2X2] · 12H2O (M=Nb, Ta; X=Cl, Br, I) wird beschrieben. Für [Nb6Br12(H2O)6][HgBr4] · 12H2O 1 und [Ta6Br12(H2O)6][HgBr4] · 12H2O 2 wurden die Strukturen röntgenographisch aus Einkristallen bestimmt: 1: kubisch, Raumgruppe Fd3m, a = 21.0072(6) Å, Z = 8, R = 0.051 (Rw = 0.066); 2: kubisch, Raumgruppe Fd3m, a = 20.9698(1) Å, Z = 8, R = 0.038 (Rw = 0.050). 1 und 2 enthalten ein oktaedrisches [M6Br12(H2O)6]2+-Cluster-Kation und ein tetraedrisches [HgBr4]2--Anion. Die M—M-Abstände betragen 2.949(1) Å für 1 und 2.9000(8) Å für 2 und die Hg—Br-Abstände 2.614(2) Å in 1 und 2.622(2) Å in 2. Die Kristallstrukturen der isotypen Clusterverbindungen 1 und 2 können mit einem dreidimensionalen Netz von H-Brücken beschrieben werden; die Kristallwassermoleküle sind Donatoren von Wasserstoffatomen zu den Bromatomen der Cluster-Kationen und zu [HgBr4]2--Anionen. Die koordinierten Wassermoleküle bilden Wasserstoffbrücken zu den Kristall-wassermolekülen. [Nb6Br12(H2O)6][HgBr4] · 12H2O ist diamagnetisch und halbleitend mit der Aktivierungsenergie, Ea = 0.20 eV.
    Notes: A method for the preparation of new solvated clusters of the composition [M6Br12(H2O)6][HgBr2X2] · 12H2O (M=Nb, Ta; X=Cl, Br, I) is given. The cubic crystals of [Nb6Br12(H2O)6][HgBr4] · 12H2O 1 and [Ta6Br12(H2O)6][HgBr4] · 12H2O 2 were characterized by the X-ray structure analysis: 1: cubic, space group Fd3m, a = 21.0072(6) Å, Z = 8, R = 0.051 (Rw = 0.066); 2: cubic, space group Fd3m, a = 20.9698(1) Å, Z = 8, R = 0.038 (Rw = 0.050). 1 and 2 contain octahedral cluster cation [M6Br12(H2O)6]2+ and tetrahedrally arranged [HgBr4]2- anion. The M—M bond distances are 2.949(1) Å for 1 and 2.9000(8) Å for 2. The Hg—Br bond distances in [HgBr4]2- anion are 2.614(2) Å in 1 and 2.622(2) Å in 2. The crystal packing patterns of the isostructural clusters 1 and 2 involve the three-dimensional hydrogen bond network; the crystalline water molecules act as donors of hydrogen to the bromine atoms of the cluster and [HgBr4]2- units, whereas the coordinated water molecules form hydrogen bonds to the crystalline water molecules. [Nb6Br12(H2O)6][HgBr4] · 12H2O is diamagnetic and semiconducting with the activation energy, Ea = 0.20 eV.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976230811
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  • 7
    Electronic Resource
    Electronic Resource
    Binary alkali metal compounds with the zintl anions [Ge9]4- and [Sn9]4-Professor Welf Bronger zum 65. Geburtstag gewidmet (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1037-1039 
    Details
    ISSN: 0044-2313
    Keywords: Alkali metal germanides and stannides ; Zintl cluster anions ; Vibrational spectra ; Thermal decomposition ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The binary germanides M12Ge17 and M4Ge9 (M = Na, K, Rb, Cs) and the stannides M12Sn17 and M4Sn9 (M = K, Rb, Cs) were identified by a combination of direct synthesis, thermogravimetric analysis, vibrational spectroscopy, X-ray powder data and single crystal structure analysis. The M12E17 phases contain the cluster anions [E9]4- and [E4]4- in the ratio 1:2, forming a hierarchical structure with the cluster anions at the atomic positions of the hexagonal Laves phase MgZn2. Like the M4E4 phases, the M4Ge9 compounds are hierarchical derivatives of the cubic Cr3Si structure but with [Ge9]4- anions. The thermogravimetric analyses give strong evidence for the existence of at least one more phase with [E9]4- and [E4]4- clusters and of the clathrate phases M6E136 in addition to the well-known M8E44□2 chlathrates.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976230704
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  • 8
    Electronic Resource
    Electronic Resource
    Phosphan-, Phosphit- und Phosphido-Komplexe des Vanadiums(V) (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1220-1228 
    Details
    ISSN: 0044-2313
    Keywords: Phosphane ; phosphite ; phosphido complexes of vanadium(V) ; syntheses ; 1H, 51V, 31P NMR ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phosphane, Phosphite, Phosphido, Complexes of Vanadium(V)Complex formation of tert-butylimidovanadium(V)trichloride (1) with phosphanes und phosphites has been studied. Syntheses of phosphidovanadium(V) compounds tC4H9N=VCp(NHtC4H9)[P(SiMe3)2] and tC4H9N=VCp(NiProp2)(PR2) (R=SiMe3, Ph) are described starting from the corresponding chlorovanadium(V) complexes. The reaction of 1 with silver hexafluorophosphate yields a bis(fluoro)phosphidovanadium(IV complex [(μ-PF2)2V2Cl2)(NtC4H9)2]; as primary intermediate product of the unknown redox reaction a cationic vanadium(V) complex [tC4H9N=VCl2 · PPh3]+PF6- has been isolated. 1 reacts with an excess of diisopropylamine forming tC4H9N=V(NiProp2)Cl2 (16); in addition the following diisopropylamido-tert-butylimidovanadium(V) compounds tC4H9N=VCp(NiProp2)Cl (3) and tC4H9N=V(NiProp2)X2 (X=CH2CMe3, OtC4H9, CH3COO) has been prepared. All compounds obtained are characterized by 1H, 51V, 31P NMR spectroscopy. The X-ray diffraction analysis of 16 and 3 indicate a planar coordination sphere of the amido nitrogen atom.
    Notes: Die Komplexbildung des tert-Butylimidovanadium(V)-trichlorids (1) mit Phosphanen und Phosphiten wurde untersucht. Die Darstellung der Phosphidovanadium(V)-Verbindungen tC4H9N=VCp(NHtC4H9)[P(SiMe3)2] und tC4H9N=VCp(NiProp2)(PR2) (R=SiMe3, Ph) wird beschrieben; als Ausgangsverbindungen werden entsprechende Chorovanadium(V)-Komplexe eingesetzt. Die Reaktion von 1 mit Silberhexafluorophosphat führt zu einem Difluorphosphidovanadium(IV)-Komplex [(μ-PF2)2V2Cl2(NtC4H9)2]; als erste Zwischenstufe der unbekannten Redoxreaktion wurde ein kationischer Vanadium(V)-Komplex [tC4H9N=VCl2 · PPh3]+PF6- isoliert. 1 reagiert mit überschüssigem Diisopropylamin unter Bildung von tC4H9N=V(NiProp2)Cl2 (16); weitere Umsetzungen lieferten die Diisopropylamido-tert-butylimido-vanadium(V)-Verbindungen tC4H9N=VCp(NiProp2)Cl (3) und tC4H9N=V(NiProp2)X2 (X=CH2CMe3, OtC4H9, CH3COO). Alle dargestellten Verbindungen werden 1H-, 51V- und 31P-NMR-spektroskopisch charakterisiert. Die Röntgenstrukturanalyse von 16 und 3 zeigt eine planare Koordinationssphäre des Amido-Stickstoffatoms.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976230807
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  • 9
    Electronic Resource
    Electronic Resource
    [Zr2Cl4(NPMe3)4(HNPMe3)] · CH3CN, ein Phosphaniminato-Komplex mit Zr=N-DoppelbindungenProfessor M. Weidenbruch zum 60. Geburtstag gewidmet (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1855-1856 
    Details
    ISSN: 0044-2313
    Keywords: Zirconium compound ; phosphorane iminato complex ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [Zr2Cl4(NPMe3)4(HNPMe3)] · CH3CN, a Phosphorane Iminato Complex with Zr=N Double BondsThe title compound has been prepared from a molten mixture of ZrCl4 with Me3SiNPMe3 in the presence of potassium fluoride and subsequent extraction with acetonitrile. According to the crystal structure determination the zirconium atoms are linked by three μ2-N atoms of two NPMe3- groups and by the HNPMe3 molecule. Two terminal bounded chlorine atoms and a terminally coordinated NPMe3- ligand complete the distorted octahedral surrounding of the zirconium atoms thus forming an edge sharing double octahedron. The ZrN bond lengths of the terminal NPMe3- groups of 194.6 pm correspond with double bonds.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976231205
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  • 10
    Electronic Resource
    Electronic Resource
    Über kristalline Natriumhydroxogallate (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1483-1488 
    Details
    ISSN: 0044-2313
    Keywords: Nonasodium bis(hexahydroxogallate) trihydroxide hexahydrate ; decasodium bis(hexahydroxogallate) tetrahydroxide ; disodium tetrahydroxogallate chloride ; crystal structure ; 71Ga MAS NMR ; 23Na MAS NMR ; DTA, DTG, guinier lenné technique ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: About Crystalline Sodium HydroxogallatesTwo crystalline sodium hydroxogallates 4,5 Na2O · Ga2O3 · 13,5 H2O (I) and 5 Na2O · Ga2O3 · 8 H2O (II), as well as a crystalline phase of the composition Na2O · Ga2O3 · 4 H2O · 2 NaCl (III) are described.
    Notes: Es werden zwei kristalline Natriumhydroxogallate 4,5 Na2O · Ga2O3 · 13,5 H2O (I) und 5 Na2O · Ga2O3 · 8 H2O (II) sowie eine kristalline Phase der Zusammensetzung Na2O · Ga2O3 · 4 H2O · 2 NaCl (III) beschrieben.(I) kristallisiert aus Natriumgallatlösungen eines breiten Konzentrationsfeldes und hat nach Einkristallröntgenstrukturanalyse [1] eine dreidimensional vernetzte Struktur aus monomeren [Ga(OH)6]3--Anionen, die über NaO6-Koordinationspolyeder untereinander verbunden sind; daneben sind Kristallwasser und weitere Hydroxidionen enthalten.Damit ist (I) als Nonanatrium-bis(hexahydroxogallat)-trihydroxid-hexahydrat (Na9[Ga(OH)6]2(OH)3 · 6 H2O) zu formulieren; Isotypie besteht zu dem entsprechenden Natriumhydroxoaluminat [2, 3]. 5 Na2O · Ga2O3 · 8 H2O II) läßt sich aus (I) in Gegenwart von Natriumhydroxid durch Entwässern über P4O10 bei Raumtemperatur unter Schutzgas (N2) erhalten. Es kristallisiert tetragonal, ist isotyp mit Na10[Al(OH)6]2(OH)4 [4] und dementsprechend als Na10[Ga(OH)6]2(OH)4 zu formulieren. Durch Zusatz von Natriumchlorid zu Natriumgallatlösungen läßt sich Na2O · Ga2O3 · 4 H2O · 2 NaCl (III) isolieren, das ebenfalls tetragonal und isotyp zu Na2[Al(OH)4]Cl [5] ist. Es handelt sich demnach um das Dinatriumtetrahydroxogallatchlorid Na2[Ga(OH)4]Cl. Die Ergebnisse der 71Ga- und 23Na-MASNMR-Messungen an den Verbindungen (I) bis (III) und deren thermisches Verhalten werden diskutiert.(I) crystallizes from sodium gallate solutions in a wide concentration field; from the X-ray single crystal diffraction analysis [1] results a three dimensional network structure, consisting of monomeric [Ga(OH)6]3- anions connected by NaO6 octahedra groups. Furthermore the structure contains water of crystallization and further hydroxide ions. (I) has to be formulated as nonasodium bis(hexahydroxogallate) trihydroxide hexahydrate Na9[Ga(OH)6]2(OH)3 · 6 H2O; it is isotypic with the corresponding sodium hydroxoaluminate [2, 3]. 5 Na2O · Ga2O3 · 8 H2O (II) was obtained from (I) in presence of sodium hydroxide by dehydration over P4O10 in an inert atmosphere (N2) at room temperature. (II) crystallizes tetragonally and is isotypic with Na10[Al(OH)6]2(OH)4 [4]. Accordingly it could be described as a decasodium bis(hexahydroxogallate) tetrahydroxide, Na10[Ga(OH)6]2(OH)4. Na2O · Ga2O3 · 4 H2O · 2 NaCl (III) was obtained by addition of sodium chloride to sodium gallate solutions, (III) crystallizes also tetragonally and is isotypic with (Na2[Al(OH)4]Cl [5]. Correspondingly, it has to be formulated as disodium tetrahydroxogallate chloride Na2[Ga(OH)4]Cl. The results of 71Ga and 23Na MAS NMR investigations of the compounds (I) to (III) and their thermal behaviour are discussed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19976230925
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