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  • Inorganic Chemistry  (134)
  • Wiley-Blackwell  (134)
  • Elsevier
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  • 1995-1999  (112)
  • 1945-1949  (22)
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 129 (1996), S. 1293-1300 
    ISSN: 0009-2940
    Keywords: Calculations, ab initio ; Aluminium compounds ; Heterometallic compounds ; Lithium compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of the simple alane adduct [Me3Al · HN(CH2Ph)2] (2) with the lithium amide [(PhCH2)2NLi] leads to the formation of the mixed adduct [Me3Al · (PhCH2)2NLi · HN(CH2Ph)2] (1). The crystal structures of 1 and 2 are reported. Exhibiting a four-membered, mixed-metal, mixedanion ring-core, the structure of 1 is unusual in containing a monomeric lithium dibenzylamide fragment. Such fragments generally convert to aza-allyl derivatives, so its existence here can be attributed to the stabilising effect of the attached Me3Al ligand. Crystalline 2 adopts the classical, distorted-tetrahedral arrangement of simple monomeric alane adducts. Ab initio MO calculations on model systems show that mixed adduct formation from Me3Al and Me2NLi is exothermic, while further reaction to give Me2AlNMe2 and MeLi (i.e., complete transmetallation) is endothermic.
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  • 2
    ISSN: 0044-2313
    Keywords: Technetium ; nitrido complexes ; crystal structure ; sulfur ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese und Charakterisierung von Bis(tetrabutylammonium) bis(isotrithiodithiolat-S,S′)nitridotechnetat(V), (Bu4N)2[TcN(dmit)2](Bu4N)2[TcN(dmit)2] (dmit2- = isotrithiodithiolat) wurde aus Na2dmit, (Bu4N)[TcNCl4] und (Bu4N)Cl in Acetonitril hergestellt. Die Verbindung kristallisiert monoklin, Raumgruppe C2/c mit a = 23,143(5), b = 8,342(2), c = 26,382(5) Å, β = 95,12(3), Z = 4. Die Bindungslänge Tc≡N beträgt 1,615(6) Å. Tc und N(l) befinden sich auf einer zweizähligen kristallographischen Achse. Der Komplex hat quadratisch-pyramidale Geometrie. Die vier Schwefelatome bilden die Grundfläche der Pyramide, deren Spitze vom Nitrido-Stickstoff eingenommen wird. Das Technetiumatom befindet sich um 0,62 Å über der Grundfläche.
    Notes: (Bu4N)2[TcN(dmit)2] (dmit2- = isotrithionedithiolate) was prepared from Na2dmit, (Bu4N)[TcNCl4] and (Bu4N)Cl in acetonitrile. The compound crystallises in the monoclinic space group C2/c with a unit cell of the dimensions a = 23.143(5), b = 8.342(2), c = 26.382(5) Å, β = 95.12(3), Z = 4. The Tc≡N bond distance is comparatively short at 1.615(6) Å. Tc and N(1) are situated on a two-fold crystallographic axis. The general coordination geometry is a square pyramid with the four sulfur atoms forming the basal plane and the nitrido nitrogen at the apex. The technetium is located 0.62 Å above the plane defined by the four sulphurs.
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  • 3
    ISSN: 0044-2313
    Keywords: Trifluoromethyliodine tetrafluoride ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Fluorinate with Trifluoromethylhypochlorite CF3OCl. Preparation and Crystal Structure Determination of Trifluoromethyliodine Tetrafluoride CF3IF4The preparation of Trifluoromethyliodine tetrafluoride (CF3IF4), from Trifluoromethyliodide (CF3I) with Trifluoromethylhypochlorite (CF3OCl), and the crystal structure of CF3IF4 at 172(1) K is described. CF3IF4 crystallizes in the monoclinic space group P21/c with a = 762.2(7) pm, b = 842.9(10) pm, c = 856.4(7) pm, β = 99.65(7)° with four formula units per unit cell.
    Notes: Es wird die Darstellung von Trifluormethyliodtetrafluorid (CF3IF4), aus Trifluormethyliodid (CF3I) und Trifluormethylhypochlorit (CF3OCl), sowie die Kristallstrukturanalyse bei 172(1) K beschrieben. CF3IF4 kristallsiert in der monoklinen Raumgruppe P21/c mit a = 762,2(7) pm, b = 842,9(10) pm, c = 856,4(7) pm, β = 99,65(7), Z = 4.
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  • 4
    ISSN: 0044-2313
    Keywords: Ferrocene ; Thioureas ; Chelates ; X-Ray Structure ; EPR-Single Crystal ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: N,N-Dialkyl-N′-ferrocenoylthioureas and Ferrocene-1,1′ -dicarbonic-acid-di-N,N-dialkylthioureides as Ligands for Transition Metals: Synthesis, Acid-Dissociation Constants, X-Ray Structure Determination, and EPR-Single Crystal InvestigationReaction of ferrocenoylisothiocyanate or ferrocene-1,1′ -dicarbonic acid -diisothiocyanate with secondary amines gives N,N-dialkyl-N′ -ferrocenoylthioureas or the respective ferrocene-1,1′-dicarbonic acid-di-N,N-dialkyl-thioureides. The former yield neutral complexes with transition metal ions (Ni2+, Cu2+, Co3+, Pt2+, Fe3+). The acid dissociation constants of the ligands were determined. The EPR spectra of a bis-(N,N-dinbutyl-N′-ferrocenoylthioureato)copper(II) single crystal are discussed. The X-ray structure determination of ferrocene-1,1′-dicarbonic acid-di-N,N-diethyl-thioureide and its different behaviour against Ni2+ and Cu2+ is presented.
    Notes: Die Reaktion von Ferrocenoylisothiocyanat bzw. Ferrocen-1,1′-dicarbonsäure-diisothiocyanat mit sekundären Aminen führt zu den entsprechenden N,N-dialkylierten N′-Ferrocenoylthioharnstoffen bzw. zu Ferrocen-1,1′-dicarbonsäure-di-N,N-dialkyl-thioureiden. Erstere bilden mit Übergangsmetallionen (Ni2+, Cu2+, Co3+, Pt2+, Fe3+) Neutralkomplexe. Die Säuredissoziationskonstanten der Liganden werden angegeben. Eine Einkristall-EPR-Untersuchung des Bis-(N,N-dinbutyl-N′ -ferrocenoylthioureato)kupfer(II) wird diskutiert. Die Röntgenkristallstrukturanalyse von Ferrocen-1,1′-dicarbonsäure-di-N,N-diethyl-thioureid und dessen unterschiedliches Verhalten gegenüber Ni2+ und Cu2+ werden erörtert.
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  • 5
    ISSN: 0044-2313
    Keywords: Copper(II) chelate complex ; iron(III) chelate complex ; edta-type ligands ; chelates ; X-ray structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molecular Structures of Copper(II) and Iron(III) Chloro Complexes with di- and monoprotonated N-(pyrid-2-ylmethyl)ethylenediamine-N,N′,N′-triacetate (H2pedta-; Hpedta2-)The molecular structures of two complexes of di- and monoprotonated N-(pyrid-2-ylmethyl)ethylenediamine-N,N′,N′ -triacetate (pedta3-) with CuII and FeIII as central atoms have been determined by single crystal X-ray diffraction methods. Both complexes have a distorted octahedral coordination with H2pedta- and Hpedta2- as pentadentate ligands and a chloride ion occupying the sixth coordination site. The different oxidation states of the central atoms result in a completely different coordination behaviour of the carboxyl groups. In both complexes one of the —CH2—COOH groups is uncoordinated. In the FeIII complex, the central atom is coordinated by the hydroxylic O atoms of the deprotonated carboxyl groups. Contrary to this in the CuII complex, the central atom is coordinated by the carbonylic O atoms. One of the coordinated carboxyl groups is protonated and the other is deprotonated. All protonated carboxyl groups in both complexes form intermolecular hydrogen bonds.
    Notes: Die Molekülstrukturen zweier Komplexe von di- bzw. monoprotoniertem N-(Pyrid-2-ylmethyl)ethylendiamin-N,N′,N′-triacetat (pedta3-) mit CuII bzw. FeIII als Zentralatome wurden durch Röntgenkristallstrukturanalyse bestimmt. Beide Komplexe haben eine verzerrt oktaedrische Koordination, in der H2pedta- bzw. Hpedta2- als fünfzähnige Liganden wirken. Die sechste Koordinationsstelle wird durch ein Chlorid-Ion besetzt. Die unterschiedliche Oxidationsstufe der Zentralatome führt zu einem unterschiedlichen Koordinationsverhalten der Carboxylgruppen. In beiden Komplexen ist eine der —CH2—COOH-Gruppen unkoordiniert. Im FeIII-Komplex erfolgt die Koordination über die hydroxylischen O-Atome der deprotonierten Carboxylgruppen. Im Gegensatz dazu beobachtet man im CuII-Komplex Koordination über die carbonylischen O-Atome, wobei eine der beiden Carboxylgruppen protoniert und die andere deprotoniert vorliegt. Von allen protonierten Carboxylgruppen in beiden Komplexen gehen intermolekulare Wasserstoffbrückenbindungen aus.
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  • 6
    ISSN: 0044-2313
    Keywords: Rhenium complexes ; carbonyl complexes ; nitrosyl complexes ; heptamethylindene ; crystal structures ; σ/η-bonding ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of Metal Carbonyls. 23. Crystal Structure and Reactivity of Heptamethylindenyl Carbonyl Metal ComplexesReaction of heptamethylindene (C9(CH3)7, 1) with Re2(CO)10 yields [η5-C9(CH3)7]Re(CO)3 (2), which reacts with NO+BF4- to form the cationic complex [{η5-C9(CH3)7}Re(CO)2NO]+BF4- (3). Irradiation of 2 with UV light in the presence of triethyl phosphite leads to formation of [η5-C9(CH3)7]Re(CO)2[P(OC2H5)3] (4). Alkylation of (CH3)3SnCl with Ind*Li gives [η1-C9(CH3)7]Sn(CH3)3 (5). All compounds were characterized by spectroscopic methods. The molecular structures of 3 and 5 were determined by single crystal X-ray diffraction (3: P21/n (14), a = 1497.7(4) pm, b = 879.0(2) pm, c = 1609.0(4) pm and β = 110.99(2)°, R1 = 0.038, wR2 = 0.080; 5: P21/n (14), a = 726.1(1) pm, b = 2930.7(3) pm, c = 930.0(1) pm and β = 112.834(5)°, R1 = 0.044, Rw = 0.048). Complexes 2-4 exhibit a piano stool configuration with a η5-coordinated permethylindenyl ligand (Ind*). Compound 5 displays a η1 -coordination of the Ind* ligand. Temperature enhancement causes a hapticity change, as observed by NMR spectroscopy.
    Notes: Heptamethylinden (C9(CH3)7H, 1) reagiert mit Re2(CO)10 zu [η5-C9(CH3)7]Re(CO)3 (2), das durch Umsetzung mit NO+BF4- die kationische Verbindung[{η5-C9(CH3)7}Re (CO)2NO]+BF4- (3) und unter Bestrahlung mit UV-Licht in Anwesenheit von Triethylphosphit [η5-C9(CH3)7]Re(CO)2[P(OC2H5)3] (4) ergibt. Durch Alkylierung von (CH3)3SnCl wird [η1-C9(CH3)7]Sn(CH3)3 (5) erhalten. Alle Verbindungen wurden mit spektroskopischen Methoden vollständig charakterisiert. Von 3 und 5 wurden die Kristallstrukturen röntgenstrukturanalytisch bestimmt (3: P21/n (14), a = 1497.7(4) pm, b = 879.0(2) pm, c = 1609.0(4) pm und β = 110.99(2)°, R1 = 0.038, wR2 = 0.080; 5: P21/n (14), a = 726.1(1) pm, b = 2930.7(3) pm, c = 930.0(1) pm und β = 112.834(5)°, R1 = 0.044, Rw = 0.048). Während bei den Komplexen 2-4 der Heptamethylindenligand (Ind*) einen Halbsandwich-Komplex bildet (η5-Bindung zum Metall), so liegt in Derivat 5 erwartungsgemäß eine σ-Bindung zwischen einem C-Atom des Ind*-Liganden und dem Metallzentrum vor. Bei Temperaturerhöhung tritt eine Änderung der Haptizitätsverhältnisse ein (NMR-Evidenz).
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  • 7
    ISSN: 0044-2313
    Keywords: Metallocene-diselenolates ; DNMR ; EPR ; X-Ray ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Characterization of Metallocene Chelates of Heterocyclic 1,2-DiselenolatesSynthesis and properties of metallocen diselenolates Cp2RML (CpR = η5-C5H4CH3 (Cp′); η5-C5(CH3)4 C2H5 (Cpo)) of titanium(IV) and vanadium(IV) with L = dsit (1,3-dithiole-2-thione-4,5-diselenolate), dsise (1,3-dithiole-2-selone-4,5-diselenolate) dsitse (1,3-thiaselenole-2-selone-4,5-diselenolate) and dsis (1,3-diselenole-2-selone-4,5-diselenolate) are described. The structures of these compounds in solution are discussed using 1H, 13C, 77Se NMR and EPR data. Their voltammetric behaviour is investigated in dichloromethane. The activation parameters of the chelate ring inversion of the titanocene diselenolates (Cp2RTiL) and the x-ray structures of Cp2′Ti(dsit), Cp2oTi(dsit); Cp2oTi(dsise) (2 modifications) and Cp2oTi(dsis) are reported.
    Notes: Synthese und Eigenschaften neuer Metallocen-Diselenolate CpR2ML (CpR = η5-C5H4CH3 (Cp′); η5C5(CH3)4C2H5 (Cpo)) des Titan(IV) und Vanadium(IV) mit L = dsit(1,3-Dithiol-2-thion-4,5-diselenolat), dsise (1,3-Dithiol-2-selon-4,5-diselenolat) dsitse (1,3-Thiaselenol-2-selon-4,5-diselenolat) und dsis (1,3-Diselenol-2-selon-4,5-diselenolat) und dsis (1,3-Diselenol-2-selon-4,5-diselenolat) werden beschrieben. Die Strukturen der Verbindungen in Lösung werden anhand der 1H-, 13C-, 77Se-NMR- und EPR-Spektren sowie ihres Redoxverhaltens diskutiert. Die durch dynamische Kernresonanzspektroskopie bestimmten Aktivierungsparameter der Chelatringinversion der Titanocen-Diselenolate (CpR2TiL), sowie die Röntgenkristallstrukturanalysen von Cp′2Ti(dsit), Cp2oTi(dsit); Cp2oTi(dsise) (2 Modifikationen) und Cp2oTi(dsise) werden vorgestellt.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 2074-2078 
    ISSN: 0044-2313
    Keywords: μ-oxo bis [pentaammine vanadium(III)] iodide monoammoniate ; μ-oxo bis [pentaammine titanium(III)] iodide monoammoniate ; preparation ; crystal structure ; IR spectroscopy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Darstellung, Kristallstruktur und IR-spektroskopische Untersuchungen an [(NH3)5V—O—V(NH3)5]I4 · NH3 und [(NH3)5Ti—O—Ti(NH3)5]I4 · NH3Reaktionen von VI2 bzw. TiI3 mit Ammoniak in Gegenwart von Wasser- bzw. Sauerstoffspuren führen zu [(NH3)5M—O—M(NH3)5]I4 · NH3 mit M = V, Ti. Ihre Strukturen wurden röntgenographisch an Einkristallen bestimmt:Pbca (Nr. 61), Z = 4, M = V: a = 12,482(4) Å, b = 14,819(6) Å, c = 13,286(5) Å, Z(Fo2 ≤ 3σFo2) = 983, Z(Variablen) = 88, R/Rw = 0,053/0,063, M = Ti: a = 12,628(4) Å, b = 14,970(4) Å, c = 13,359(3) Å, Z(Fo2 ≤ 3σFo2) = 1188, Z(Variablen) = 88, R/Rw = 0,043/0,047Die Strukturen bauen sich aus Oktaederdoppeleinheiten [(NH3)5M—O—M(NH3)5]4+ mit ekliptischer Konformation auf, deren verbrückende Sauerstoffatome nach dem Motiv einer verzerrten, kubisch flächenzentrierten Packung angeordnet sind. IR-spektroskopische Daten von undeuterierten und zu 5% deuterierten Proben der Vanadiumverbindung weisen auf N—H … I-Wasserstoffbrückenbindungen und π-Bindungsanteile zwischen dem jeweiligen Übergangsmetall und dem verbrückenden Sauerstoffatom hin.
    Notes: The reaction of VI2 or TiI3, respectively, with ammonia in the presence of traces of water or oxygen, respectively, leads to [(NH3)5M—O—M(NH3)5]I4 · NH3 with M = V, Ti. Their structures were solved by X-ray single crystal data:Pbca (No. 61), Z = 4, M = V: a = 12.482(4) Å, b = 14.819(6) Å, c = 13.286(5) Å, N(Fo2 ≤ 3σFo2) = 983, N(variables) = 88, R/Rw = 0.053/0.063, M = Ti: a = 12.628(4) Å, b = 14.970(4) Å, c = 13.359(3) Å, N(Fo2 ≤ 3σFo2) = 1188, N(variables) = 88, R/Rw = 0.043/0.047.The structures consist of corner sharing octahedra double units [(NH3)5M—O—M(NH3)5]4+ with eclipsed conformation which are stacked together according to the motif of a distorted cubic face centered arrangement for the bridging oxygen atoms. IR spectroscopic investigations of the undeuterated vanadium compound and of 5% deuterated samples hint to N—H … I hydrogen bridge bonds and to remarkable π-bonding between the transition metal and the bridging oxygen atoms.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 713-718 
    ISSN: 0044-2313
    Keywords: New Lithogermanate ; crystal structure ; MAPLE, CHARDI calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The First Oxogermanate with “Stuffed Pyrgoms”: CsNa3Li8{Li[GeO4]}4By heating the binary oxides CsO0.52, NaO0.45, LiO0.5 and GeO2 in the mol. ratio 1.24:1.4:6.7:3.9 (Ni tubes; 600°C/89 resp. 65 d) we obtained for the first time CsNa3Li8{Li[GeO4]}4 in form of pale yellow prisms as well as powder: space group I4/m (I. T. No. 87) with a = 1 120.73(5); c = 651.64(5) pm; Z = 2; (four circle diffractometer data; MoKα; 5 152 Io(hkl); R = 1.7%; Rw = 1.6%), parameters see text. The structure determination confirmes its being isotypic with CsKNaLi9{Li[SiO4]}4, CsKNa2Li8{Li[SiO4]}4 and RbNa3Li8{Li[SiO4]}4. The Madelung part of lattice energy (MAPLE), effective coordination numbers (ECoN), mean fictive ionic radii (MEFIR) and the charge distribution (CHARDI) are calculated.
    Notes: Durch Tempern der binären Oxide CsO0,52, NaO0,45, LiO0,5 und GeO2 im mol. Verhältnis 1,24:1,4:6,7:3,9 (Ni-Bömbchen; 600°C/89 bzw. 65 d) wurden erstmals Einkristalle von CsNa3Li8{Li[GeO4]}4 in Form von schwachgelblichen Prismen sowie blaßgelbem Pulver erhalten: Raumgruppe I4/m (I. T. Nr. 87) mit a = 1 120,73(5); c = 651,64(5) pm; Z = 2; (Vierkreisdiffraktometerdaten; Mo-Kα; 5 152 Io(hkl); R = 1,7%; Rw = 1,6%), Parameter siehe Text. Die Strukturbestimmung belegt die Isotypie mit CsKNaLi9{Li[SiO4]}4, CsKNa2Li8{Li[SiO4]}4 und RbNa3Li8{Li[SiO4]}4. Ferner werden der Madelunganteil der Gitterenergie (MAPLE), Effektive Koordinationszahlen (ECoN), Mittlere Fiktive Ionenradien (MEFIR) und die Ladungsverteilung (CHARDI) berechnet.
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  • 10
    ISSN: 0044-2313
    Keywords: Th2Ta6O19 ; LaNb7O19 ; chemical transport ; crystal structure ; “Jahnberg-structure-family” ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Crystal Structure of Th2Ta6O19, the First Example of a “Jahnberg-Structure” with M = M4+ (M = Th4+); with a Note to LaNb7O19Colorless, hexagonal crystals of Th2Ta6O19 were obtained by chemical transport in the temperature gradient 1000°C → 980°C using a mixture of ThO2, ZrO2 (or HfO2) and Ta2O5 (1 : 2 : 2) as starting material and Cl2, ZrCl4 or HfCl4 as transport agents. The lattice constants are a = 6.275(1) Å, c = 19.968(6) Å and Z = 2. Structure determination in the space group P63/mcm (no. 193) let to R1 = 0.032 (wR2 = 0.074). Thorium is surrounded by oxygen like an transbis-capped octahedron (CN = 8) and tantalum like a pentagonal bipyramid (CN = 7).Both coordination polyhedra are for themself arranged to layers (Th to o-, Ta to p-layers) so that in the direction of the c-axes a sequence of layers like p-p-o-p-p-o appears. Therefore the compound is a new representative of the structures described by Jahnberg.
    Notes: Durch chemischen Transport, ausgehend von Gemengen aus ThO2, ZrO2 (bzw. HfO2) und Ta2O5 (1 : 2 : 2) und mit Cl2, ZrCl4 oder HfCl4 als Transportmittel, wurden im Temperaturgefälle 1000°C → 980°C farblose, hexagonale Einkristalle von Th2Ta6O19 mit den Gitterkonstanten a = 6,275(1) Å, c = 19,968(6) Å und Z = 2 erhalten. Die Strukturaufklärung in der Raumgruppe P63/mcm (Nr. 193), die bei R1 = 0,032 (wR2 = 0,074) konvergierte, ergab für Th CN = 8 und Ta CN = 7. Thorium ist in Form eines transbis-bekappten Oktaeders, Tantal pentagonal-bipyramidal von Sauerstoff umgeben.Beide Koordinationspolyeder sind für sich in Schichten (Th in o-, Ta in p-Schicht) so angeordnet, daß sich eine Schichtabfolge p-p-o-p-p-o in c-Richtung ergibt. Demnach ist die Verbindung als neue Variante der von Jahnberg beschriebenen Strukturen anzusehen.
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