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  • 1
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: X-Ray Studies on Titanium(III) Fluoro Compounds with Pyrochlore-related StructuresThe cubic compounds (a/pm) CsMIITiIIIF6, MII = Mg (1041.6), Ni (1043.9), Zn (1049.8), Co (1051.7), V (1052.6), Fe (1055.3), Mn (1064.9) and CsM0,5ITi1,5IIIF6, MI = K (1074.6), Rb (1080.6) were prepared. They crystallize in the modified pyrochlore structure of the RbNiCrF6 type, which is confirmed once more at single crystals of an oxide fluoride phase CsTi2X6 (X6 between O2F4 and O3F3): Space group Fd3m, a = 1028.8 pm, R = 2.6% (126 independent reflections). Further compounds CsM0,5ITi1,5IIIF6 according to their powder diagrams are orthorhombic (MI = NH4: a = 764.1, b = 767.5, c = 1087.5 pm) or monoclinic (Na: a = 737.0, b = 758.0, c = 1061.8 pm, β = 91.1°, Li: a = 1466, b = 1479, c = 1041 pm, β = 93.3°) with related, but not exactly know structures.
    Notes: Die kubischen verbindungen (a/pm) CsMIITiIIIF6, MII = Mg(1041,6), Ni(1043,9), Zn(1049,8), Co(1051,7), V(1052,6), Fe(1055,3), Mn(1064,9) und CsM0,5ITi1,5IIIF6, MI = K(1074,6), Rb(1080,6) wurden dargestellt. Sie kristallisieren in der modifizierten Pyrochlorstruktur des RbNiCrF6-Types, der an Einkristallen einer Oxidfluoridphase CsTi2X6 (X6 zwischen O2F4 und O3F3) erneut bestätigt wird: Raumgruppe Fd3m, a = 1028,8 pm, R = 2,6% (126 symmetrieunabhängige Reflexe). Weitere Verbindungen CsM0,5ITi1,5IIIF6 sind nach Pulveraufnahmen orthorhombisch (MI = NH4: a = 764,1, b = 767,5, c = 1087,5 pm) bzw. monoklin (Na: a = 737,0, b = 758,0, c = 1061,8 pm, β = 91,1°, Li: a = 1466, b = 1479, c = 1041 pm,β = 93,3°), mit verwandten, aber nicht genauer bekannten Strukturen.
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  • 2
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: X-Ray Single Crystal Structure Determinations of the Potassium Copper(II) Fluorides K2CuF4 and K3Cu2F7With single crystals of the tetragonal compounds K2CuF4 (a = 414.7(2), c = 1273(3) pm) and K3Cu2F7 (a = 415.6(3), c = 2052(3) pm), showing no superstructure reflections, crystal structure determinations were based on space group I4/mmm of the K2NiF4 and Sr3Ti2O7 type, resp. The shape of F0-Fourier maxima at the positions of linking fluorine atoms within the layers of octahedra suggested disorder of bridging ligands caused by multidomain structure, which could be refined assuming half occupation of higherfold positions. The results confirmed the Jahn-Teller-distortions of octahedra being elongated with a significant orthorhombic component: Cu—F = 190.9(7)/193.9(2)/223.8(7) pm in K2CuF4 (RW = 0.020) and 190.0(7)/194.7/225.6(7) pm in K3Cu2F7 (RW = 0.023). In the acentric octahedra of the latter compound the intermediate distance is averaged from the splitted lengths 192.7(4)/196.8(1) pm of axes along the c direction.
    Notes: Von Einkristallen der tetragonalen Verbindungen K2CuF4 (a = 414,7(2), c = 1273(3) pm) und K3Cu2F7 (a = 415,6(3), c = 2052(3) pm), die röntgenographisch keine Überstrukturreflexe zeigten, wurden die Kristallstrukturen unter Zugrundelegung der Raumgruppe I4/mmm des K2NiF4- bzw. Sr3Ti2O7-Typs bestimmt. Aus den Formen der F0-Fouriermaxima an den Stellen der die Oktaeder zu Schichten verknüpfenden Fluoratome wurde auf Fehlordnung der Brükkenliganden geschlossen, die von einer Multidomänenstruktur herrührt und unter Annahme halbbesetzter höherzähliger Punktlagen verfeinert werden kann. Das Ergebnis bestätigte die Jahn-Teller-Verzerrung zu gestreckten Oktaedern mit signifikanter orthorhombischer Komponente: Cu—F = 190,9(7)/193,9(2)/223,8(7) pm in K2CuF4 (RW = 0,020) und 190,0(7)/194,7/225,6(7) pm in K3Cu2F7 (RW = 0,023). In den azentrischen Oktaedern der letztgenannten Verbindung setzt sich der mittlere Abstand aus entlang der c-Richtung aufgespaltenen Achslängen von 192,7(4)/196,8(1) pm zusammen.
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  • 3
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Relations of Distances and Coordination in the Layer Structures of the Ternary Fluorides K2MF4 and K3M2F7 (MII = Mg, Mn, Co=Zn)Results of X-ray single crystal structure refinements of the compounds K2MF4 (M = Mg, Mn, Co, Ni) and K3M2F7 (M = Mn, Co, Ni), all crystallizing in the tetragonal space group I4/mmm of the K2NiF4 and Sr3Ti2O7 type, resp., are reported. The distances obtained are discussed, including data of the compounds with M = Cu, Zn. The influence of the KF9 coordination is made responsible for the fact, that the octahedral MF6 dimensions are much the same as in the corresponding perovskites KMF3. The shortest K—F distance of this KF9 group, occuring in both layer structure types, decreases against lattice widening from 263.4 pm (K2MgF4) to 258.0 pm (K2MnF4). The charge ratio calculated from the KF9 coordination for the unlike bonded anions leads to a better balanced charge distribution in the K2MF4 type, as is obtained by applying Pauling's rules.
    Notes: Ergebnisse röntgenographischer Einkristallstrukturverfeinerungen an den im K2NiF4- bzw. Sr3Ti2O7-Typ kristallisierenden Verbindungen K2MF4 (M = Mg, Mn, Co, Ni) und K3M2F7 (M = Mn, Co, Ni), die alle der tetragonalen Raumgruppe I4/mmm angehören, werden mitgeteilt. Die resultierenden Abstandsdaten werden unter Einbeziehung der Verbindungen mit M = Cu, Zn diskutiert. Die weitgehend den zugehörigen Perowskiten KMF3 entsprechenden Abstandsverhältnisse in den MF6-Oktaedern werden dem Einfluß der KF9-Koordination zugeschrieben, deren kürzester Abstand K—F in beiden Schichtstrukturtypen entgegen der Gitteraufweitung von 263,4 pm (K2MgF4) auf 258,0 pm (K2MnF4) abnimmt. Das aus der KF9-Koordination berechnete Ladungsverhältnis der ungleich gebundenen Anionen führt zu einer ausgeglicheneren Ladungsbilanz für den K2MF4-Typ, als die Anwendung der Paulingschen Regeln.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 505 (1983), S. 153-160 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Lattice Constants and Ionic Radii of Pyrochlores CsMIIMIIIF6From observed lattice constants a0 of 30 cubic pyrochlores CsMIIMIIIF6 (MII = Mg, Ni, Cu, Zn, Co, Mn; MIII = Ga, Cr, Fe, V, Ti) balanced values ac were calculated, which deviate in average less than 0.1% from the observed ones. Radii rc of the M(II) and M(III) ions are evaluated from the balanced values ac by means of an empiric equation; they reproduce the lattice constants a0 equally well. By analogy derived radii rII and rIII from additional pyrochlores CsMIIMIIIF6 are given and discussed in comparison with tabulated radii and observed M—F distances.
    Notes: Aus den beobachteten Gitterkonstanten a0 von 30 kubischen Pyrochloren CsMIIMIIIF6 (MII = Mg, Ni, Cu, Zn, Co, Mn; MIII = Ga, Cr, Fe, V, Ti) werden Ausgleichswerte ac gebildet, die im Mittel weniger als 0,1% von den Beobachtungsgrößen abweichen. Aus den Ausgleichswerten ac werden mit Hilfe einer empirischen Beziehung Radien rc für die M(II)- und M(III)-Ionen abgeleitet, mit denen die Gitterkonstanten a0 mit entsprechender Genauigkeit reproduzierbar sind. Analog aus weiteren Pyrochloren CsMIIMIIIF6 ermittelte Radien rII und rIII werden mitgeteilt und im Vergleich mit tabellierten Radien und beobachteten M—F-Abständen diskutiert.
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  • 5
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structures of Caesium-containing Fluorides. VII. Cs6Ni5F16 - a New Compound in the System CsF/NiF2 and its Crystal StructureSingle crystals of a more caesium-containing phase of composition Cs6Ni5F16, forming in the course of solid state CsNiF3 preparation, could be isolated and their structure determined: a = 618.4(1), b = 1. 455.5(2), c = 2145.1(2) pm, space group Cmca, Z = 4, R = 0.030 (1936 independent reflections). The structure contains chains of five face-sharing octahedra, which are connected at their ends via corners to form a zig-zag layer. The Ni—Ni distances within the chains are 264.1 and 270.2 pm, the average Ni—F distance is 202.0 pm. The caesium atoms exhibit 10-, 11-, and 12-coordination. The structural relations to 2L—CsNiF3 and Cs4Ni3F10 are discussed.
    Notes: Eine bei der Darstellung von CsNiF3 durch Festkörperreaktion auftretende caesiumreichere Phase der Zusammensetzung Cs6Ni5F16 konnte in Form von Einkristallen isoliert und röntgenographisch ihre Struktur bestimmt werden: a = 618,4(1), b = 1455,5(2), c = 2145,1(2) pm, Raumgruppe Cmca, Z = 4, R = 0,030 für 1936 unabhängige Reflexe. Die Struktur enthält Ketten von fünf flächenverknüpften Oktaedern, die an ihren Enden über Ecken zu einer gewellten Schicht verbunden sind. Die Ni—Ni-Abstände in den Ketten betragen 264,1 und 270,2 pm, der mittlere Ni—F-Abstand 202,0 pm. Für die Caesiumatome werden Koordinationszahlen von 10, 11 und 12 beobachtet. Die strukturellen Beziehungen zu 2L-CsNiF3 und Cs4Ni3F10 werden erläutert.
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  • 6
    ISSN: 0044-2313
    Keywords: Antimony(V)-oxide chloride ; Synthesis ; IR Spectra ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, IR Spectrum, and Crystal Structure of Sb12O18(OH)2Cl22 · 2CH2Cl2The title compound has been prepared by the reaction of Sb5O7Cl11 with dichloromethane at 20°C, forming colourless, moisture sensitive crystals. Sb12O18(OH)2Cl22 · 2CH2Cl2 crystallizes monoclinically in the space group P21/n with two formula units per unit cell. Structure solution with 2696 unique observed reflections, R = 0.042. Lattice dimensions at 19°C: a = 1350.2, b = 1466.7, c = 1392.9 pm, b̃ = 97.925°. The distorted octahedrally coordinated antimony atoms, bridged by oxygen atoms, exhibit a molecular array which may be seen as a fragment of the rutile type structure, isolated by terminal chloride ligands. The solvate molecule is associated by a hydrogen bridge OH···Cl.
    Notes: Die Titelverbindung entsteht in Form farbloser Kristalle bei der Reaktion von Sb5O7Cl11 mit Dichlormethan bei 20°C. Sb12O18(OH)2Cl22 · 2CH2Cl2 kristallisiert monoklin in der Raumgruppe P21/n mit zwei Formeleinheiten pro Elementarzelle. Strukturlösung mit 2696 unabhängigen beobachteten Reflexen, R = 0,042. Gitterkonstanten bei 19°C: a = 1350,2; b = 1466,7; c = 1392,9 pm, b̃ = 97,925°. Die verzerrt oktaedrisch koordinierten und über Sauerstoffatome verbrückten Antimonatome bilden ein molekulares Gerüst, das als ein durch terminale Chlorliganden isolierter Ausschnitt aus der Rutilstruktur angesehen werden kann. Das Solvatmolekül ist durch eine Wasserstoffbrücke OH…Cl assoziiert.
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  • 7
    ISSN: 0044-2313
    Keywords: Weberite structure ; structure determination ; di-sodium iron vanadium hepta-fluoride ; di-sodium iron chromium hepta-fluoride ; di-sodium cobalt vanadium hepta-fluoride ; disodium cobalt chromium hepta-fluoride ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal Structure Determinations of Four Monoclinic Weberites Na2MIIMIIIF7 (MII = Fe, Co; MIII = V, Cr)By solid state reaction of the binary fluorides single crystals of the following weberites were prepared and their monoclinic structure (space group C2/c, Z = 16) determined by X-ray methods: Na2FeVF7 (a = 1 271.0(3), b = 742.9(1), c = 2 471.6(5) pm, β = 100.03(3)°; R1 = 0.043 (1 545 Reflexe); Fe—F = 203.8, V—F = 193.0 pm); Na2FeCrF7 (a = 1 262.5(3), b = 739.1(1), c = 2 460.5(5) pm, β = 99.93(3)°; R1 = 0.029 (2 340); Fe—F = 203.6, Cr—F = 190.5 pm); Na2CoVF7 (a = 1 270.3(5), b = 739.1(3), c = 2 465.1(10) pm, β = 100.02(3)°; R1 = 0.028 (2 250); Co—F = 201.6, V—F = 193.6 pm); Na2CoCrF7 (a = 1 257.8(3), b = 733.5(1), c = 2 441.5(5) pm, β = 99.64(3)°; R1 = 0.030 (2 227); Co—F = 201.2, Cr—F = 190.2 pm). Concerning the above average distances within the distorted [MF6] octahedra and the shape of [NaF8] coordination details are given and discussed.
    Notes: Durch Festkörperreaktion der binären Fluoride wurden Einkristalle der folgenden Weberite dargestellt und röntgenographisch deren monokline Struktur bestimmt (Raumgruppe C2/c, Z = 16): Na2FeVF7 (a = 1 271,0(3), b = 742,9(1), c = 2 471,6(5) pm, β = 100,03(3)°; R1 = 0,043 (1 545 Reflexe); Fe—F = 203,8, V—F = 193,0 pm); Na2FeCrF7 (a = 1 262,5(3), b = 739,1(1), c = 2 460,5(5) pm, β = 99,93(3)°; R1 = 0,029 (2 340); Fe—F = 203,6, Cr—F = 190,5 pm); Na2CoVF7 (a = 1 270,3(5), b = 739,1(3), c = 2 465,1(10) pm, β = 100,02(3)°; R1 = 0,028 (2 250); Co—F = 201,6, V—F = 193,6 pm); Na2CoCrF7 (a = 1 257,8(3), b = 733,5(1), c = 2 441,5(5) pm, β = 99,64(3)°; R1 = 0,030 (2 227); Co—F = 201,2, Cr—F = 190,2 pm). Zu den genannten mittleren Abständen in den verzerrten [MF6]-Oktaedern und zur Form der [NaF8]-Koordination werden Einzelheiten mitgeteilt und diskutiert.
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  • 8
    ISSN: 0044-2313
    Keywords: Structure determination ; [FeO5] square pyramide ; asymmetric [PbO6] coordination ; lone pair effect ; perovskite relation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Lead Strontium Ferrate(III): The Crystal Structure of the Phase Pb4Sr2Fe6O15At orthorhombic single crystals of Pb4Sr2Fe6O15 (a = 568.73(8), b = 392.03(4), c = 2107.5(3) pm; Z = 4/3, space group Pnma) a X-ray structure determination has been performed (R1 = 0,036 for 488 „observed“ resp. wR2 = 0,073 for all 643 independent reflexions). It revealed a framework of polyhedra related to perovskite, in which chains of edgesharing pyramids [FeO5] (average Fe1—O: 197 pm; Fe1—Fe1: 305.5 pm) are linked via apices with corner-sharing [FeO6] octahedra (Fe2—O: 201 pm). 12-fold, strongly distorted cuboctahedrally coordinated „perovskite positions“ show mixed occupancy by 2/3 Sr + 1/3 Pb (= Sr2; Sr2—O: 287 pm). More spacy channels, running parallel to the chains of pyramids along [010] of the structure, contain lead atoms only. The double occupancy of the corresponding cages results in short distances Pb1—Pb1 (355.9 pm) and Pb1—Fe2 (314.4 pm), as well as in a very asymmetric [PbO6] coordination (Pb1—O: 253 pm), in the opposite hemisphere of which the lone electron pair s2 is supposed to be located. Details are communicated and structural relations discussed.
    Notes: An orthorhombischen Einkristallen von Pb4Sr2Fe6O15 (a = 568,73(8), b = 392,03(4), c = 2107,5(3) pm; Z = 4/3, Raumgruppe Pnma) wurde eine Röntgenstrukturbestimmung durchgeführt (R1 = 0,036 für 488 „beobachtete“ bzw. wR2 = 0,073 für alle 643 unabhängigen Reflexe). Diese ergab ein perowskitverwandtes Polyedergerüst, in dem Ketten kantenverknüpfter [FeO5]-Pyramiden (Mittelwert Fe1—O: 197 pm; Fe1—Fe1: 305,5 pm) mit ihrerseits eckenverknüpften [FeO6]-Oktaedern (Fe2—O: 201 pm) über Ecken verbunden sind. Zwölffach, stark verzerrt kuboktaedrisch koordinierte „Perowskit-Positionen“ sind gemischt besetzt mit 2/3 Sr + 1/3 Pb (= Sr2; Sr2—O: 287 pm). Dagegen befinden sich in größeren Kanälen, die sich parallel zu den Pyramidenketten längs [010] durch die Struktur ziehen, nur Bleiatome. Die doppelte Besetzung der zugehörigen Hohlräume führt zu kurzen Abständen Pb1—Pb1 (355,9 pm) und Pb1—Fe2 (314,4 pm), und zu einer ganz einseitigen [PbO6]-Koordination (Pb1—O: 253 pm). in deren Gegenhemisphäre das s2-Elektronenpaar zu vermuten ist. Einzelheiten werden mitgeteilt und Strukturverwandtschaften diskutiert.
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  • 9
    ISSN: 0044-2313
    Keywords: Structure determination ; vanadium weberites ; disodium metal(II) vanadium(III) heptafluorides ; sodium tetrafluoro-vanadate(III) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structures of the Vanadium Weberites Na2MIIVIIIF7 (MII = Mn, Ni, Cu) and of NaVF4At single crystals of the vanadium(III) compounds NaVF4 (a = 790.1, b = 531.7, c = 754.0 pm, β = 101.7°; P21/c, Z = 4), Na2NiVF7 (a = 726.0, b = 1031.9, c = 744.6 pm; Imma, Z = 4) and Na2CuVF7 (a = 717.6, b = 1043.5, c = 754.6 pm; Pmnb, Z = 4) X-ray structure determinations were performed, at Na2MnVF7 (a = 746.7, c = 1821.6 pm; P3221, Z = 6) a new refinement. NaVF4 crystallizes in the layer structure type of NaNbO2F2. The fluorides Na2MIIVF7 represent new orthorhombic (MII = Ni; Cu) resp. trigonal (MII = Mn) weberites. The average distances within the [VF6] octahedra of the four compounds are in good agreement with each other and with data of related fluorides (V—F: 193.3 pm). The differences between mean bond lengths of terminal and bridging F ligands are 5% in NaVF4, but less than 1% in the weberites. Details and data for comparison are discussed.
    Notes: An Einkristallen der Vanadium(III)-Verbindungen NaVF4 (a = 790,1, b = 531,7, c = 754,0 pm, β = 101,7°; P21/c, Z = 4), Na2NiVF7 (a = 726,0, b = 1031,9, c = 744,6 pm; Imma, Z = 4) und Na2CuVF7 (a = 717,6, b = 1043,5, c = 754,6 pm; Pmnb, Z = 4) wurden Röntgenstrukturbestimmungen durchgeführt, an Na2MnVF7 (a = 746,7, c = 1821,6 pm; P3221, Z = 6) eine neue Verfeinerung. NaVF4 kristallisiert in der Schichtstruktur des NaNbO2F2-Typs. Die Fluoride Na2MIIVF7 sind neue orthorhombische (MII = Ni; Cu) bzw. trigonale (MII = Mn) Weberit-Vertreter. Die mittleren Abstände in den [VF6]-Oktaedern der vier Verbindungen stimmen gut miteinander und mit Daten in verwandten Fluoriden überein (V—F: 193,3 pm). Die Unterschiede zwischen den mittleren Abständen terminaler und verbrückender F-Liganden betragen in NaVF4 5%, in den Weberiten aber weniger als 1%. Einzelheiten und Vergleichsdaten werden diskutiert.
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  • 10
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Refinement of the 12L Structure of the Hexagonal-rhombohedral Elpasolite Rb2LiFeF6The single crystal structure determination of the hexagonal Elpasolite Rb2LiFeF6 confirmed (R = 2.4%) the compound to be isotypic to the hexagonal-rhombohedral 12 layer structure of the Cs2NaCrF6 type. The compound crystallizes with a = 588.0(3), c = 2879.0(8) pm (a = 1017.9 pm, α = 33.57°) in space group R3m. The fluorine distances of the two iron atoms differing in distortion of their octahedral coordination are 191.9(3) and 193.6(3) pm, resp. By face-sharing with FeF6 octahedra at one side and edge-sharing at the other, the LiF6 octahedra are strongly deformed, Li—F = 200.8/223.1(13), Li—Fe = 281.0(18) pm. Both rubidium atoms are 12 coordinated, average distance Rb—F = 297.7 pm. The relations of hexagonal-rhombohedral lattice constants to those of a pseudomonoclinic cell, as claimed for some Elpasolites, are pointed out.
    Notes: Die Einkristallstrukturbestimmung an dem hexagonalen Elpasolith Rb2LiFeF6 bestätigte (R = 2,4%) die Isotypie mit der hexagonal-rhomboedrischen 12-Schichtenstruktur des Cs2NaCrF6-Typs. Die Verbindung kristallisiert mit a = 588,0(3), c = 2879,0(8) pm (a = 1017,9 pm, α = 33,57°) in der Raumgruppe R≙m. Die Fluorabstände der beiden mit unterschiedlichem Verzerrungsgrad oktaedrisch koordinierten Eisenatome betragen Fe—F = 191,9(3) bzw. 193,6(3) pm. Durch die Flächenverknüpfung mit FeF6-Oktaedern auf der einen, Eckenverknüpfung auf der anderen Seite sind die LiF6-Oktaeder stark deformiert, Li—F = 200,8/223,1(13), Li—Fe = 281,0(18) pm. Die beiden Rubidiumatome sind 12fach koordiniert, Mittelwert Rb—F = 297,7 pm. Auf die Beziehungen hexagonal-rhomboedrischer Gitterkonstanten zu denen einer pseudomonoklinen Zelle, wie sie für manche Elpasolithe angegeben wurde, wird hingewiesen.
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