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  • Chemistry  (14)
  • Cesium copper(II) fluoride, CsCu2F5  (1)
  • Copper weberites, Na2CuGaF7, Na2CuInF7  (1)
  • Cyano-elpasolites  (1)
  • antiferromagnetism  (1)
  • bis(-tetramethylammonium) alkali hexacyanometallates  (1)
  • IR Spectra
  • 1990-1994  (11)
  • 1975-1979  (3)
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Keywords
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Year
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 442 (1978), S. 151-162 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structures of Fluorides with Caesium. IV. The Crystal Structure of CsCrF4 - a Novel Tetra-fluorometallate Type with Chain StructureThe crystal structure of the hexagonal compound CsCrF4, crystallizing in space group P62m-D3h3, was determined: a =9.650(5), c = 3.857(3) Å, z = 3, R = 0.023 for 220 symmetrically independent reflections hkl. CsCrF4 is a new type of chain structure, containing three chains of octahedra sharing trans corners along [001] and connected by cis corners to form a triple chain. The bridging angles are Cr—F—Cr = 177.9° and 149.3°, the corresponding distances Cr—F = 1.929 and 1.940 Å, resp., compared to 1.851 Å for the terminal ligands. The results are discussed and relations to other structures shown.
    Notes: Die Kristallstruktur der hexagonal in der Raumgruppe P62,-D3h3 krikristallisierenden Verbindung CsCrF4 wurde bestimmt: a = 9,650(5), c = 3,857(3) Å, V = 311,1 Å3, z = 3, R = 0,023 für 220 symmetrieunabhängige Reflexe hkl. CsCrF4 stellt eine neuen Typ von Kettenstruktur dar, in dem drei längs [001] über trans-Ecken verknüpfte Oktaederketten miteinander über cis-Ecken zu einem Dreierstrang verbunden sind. Die Brückenwinkel betragen Cr—F—Cr 177,9° bzw. 149,3°, die entsprechenden Abstände Cr—F = 1,929 bzw. 1,940 Ä, gegenüber 1,851 Å für die terminalen Liganden. Die Ergebnisse werden diskutiert und Beziehungen zu anderen Strukturen aufgezeigt.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 418 (1975), S. 193-207 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: High Pressure Syntheses and Transformations of Hexagonal Elpasolithes A2IBIMIIIF6Hexagonal-rhombohedrally in the structure type of Cs2NaCrF6 crystallizing elpasolithes Rb2LiMF6 and Cs2NaMF6 (MIII = Al, Ga, V, Cr, Fe) were transformed to cubic modifications (K2NaAlF6 type) by high pressure application (15-100 kbar). In addition intermediate high pressure phases with the hexagonal structure of high temperature K2LiAlF6 could be obtained in some cases. The lattice constants of these compounds are reported, as well as those of hexagonal elpasolithes Tl2LiMF6 and Cs2LiMF6 which only form, if they are synthesized under pressure. The results are discussed in connection with the Goldschmidt tolerance factor t′ = √2(rA + rF)/(rB + rM + 2rF) of the elpasolithes mentioned.
    Notes: Von hexagonal-rhomboedrisch im Cs2NaCrF6-Typ kristallisierenden Elpasolithen Rb2LiMF6 und Cs2NaMF6 (MIII = Al, Ga, V, Cr, Fe) konnten durch Hochdruckanwendung (15-100 kbar) kubische Modifikationen (K2NaAlF6-Typ) erhalten werden. Als intermediäre Hochdruckphasen ließen sich in einigen Fällen außerdem Modifikationen mit der hexagonalen Struktur von Hochtemperatur-K2LiAlF6 fassen. Die Gitterkonstanten dieser Verbindungen werden mitgeteilt, ebenso wie diejenigen neuer hexagonaler Elpasolithe Tl2LiMF6 und Cs2LiMF6, die sich nur bilden, wenn die Synthese unter Druck erfolgt. Die Ergebnisse werden im Zusammenhang mit dem Goldschmidtschen Toleranzfaktor t′ = √2(rA + rF)/(rB + rM + 2rF) der genannten Elpasolithe diskutiert.
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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: Structures of Cesium-containing Fluorides. V. Pseudohexagonal Tungsten Bronze Structure of the Monoclinic Phase Cs0.4Zn0.4Fe1.6F6 and Related Cesium Transition Metal FluoridesThe crystal structure of the pseudohexagonale phase Cs0.4Zn0.4Fe1.6F6 was refined in the monoclinic space group P21 (a = 747.4, b = 763.6, c = 746.1 pm, β = 120.0°, z = 3). Using 1067 single crystal reflections R = 6.3% was reached. Compared to the hexagonal tungsten bronze structure the corner-sharing of octahedra shows pronounced angles also along the unique axis (M—F—M = 159.0°). The average bridge angle in the framework of tilted octahedra is 149.6°. Structural relations are discussed.
    Notes: Die Kristallstruktur der pseudohexagonalen Phase Cs0,4Zn0,4Fe1,6F6 konnte in der monoklinen Raumgruppe P21 (a = 747,4 b = 763,6, c = 746,1 pm, β = 120,0°, z = 3) unter Auswertung von 1 067 Einkristallreflexen auf R = 6,3% verfeinert werden. Im Vergleich zur Struktur der hexagonalen Wolframbronzen ist die Oktaeder-Eckenverknüpfung auch längs der ausgezeichneten Achse deutlich gewinkelt (M—F—M = 159,0°). Der mittlere Brückenwinkel im Raumnetz der verkippten Oktaeder beträgt 149,6°. Die Strukturverhältnisse werden diskutiert.
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  • 4
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Jahn-Teller Effect and Crystal Structure Distortion of the Copper Fluoroperovskites NaCuF3 and RbCuF3The crystal structures of triclinic NaCuF3 (a = 539.1, b = 555.2, c = 792.8 pm, α = 90.66, β = 92.05, γ = 86.95°; P1, Z = 4) and of tetragonal RbCuF3, isotypic with KCuF3, (a = 602.3, c = 791.2 pm; I4/mcm, Z = 4), were determined by x-ray methods and refined to wR = 0.038 (2113 reflections) resp. 0.039 (257 reflections). The structures derive from orthorhombic (GdFeO)3 and cubic perovskite type, resp., by Jahn-Teller distortion. The CuF64- octahedra, differently elongated in the two compounds (average NaCuF3: Cu—F = 188.9/197.3/225.6(2) pm; RbCuF3: 188.3/197.8/237.6(3) pm), show the same pattern of antiferrodistortive ordering, but there are bent bridges Cu—F—Cu = 144.2…148.0(1)° in NaCuF3. Structural relations to the prototypes mentioned and to comparably Jahn-Teller distorted copper fluoro compounds are discussed.
    Notes: Die Kristallstrukturen des triklinen NaCuF3 (a = 539,1, b = 555,2, c = 792,8 pm, α = 90,66, β = 92,05, γ = 86,95°; P1, Z = 4) und des tetragonalen, mit KCuF3 isotypen RbCuF3 (a = 602,3, c = 791,2 pm; I4/mcm, Z = 4) wurden röntgenographisch bestimmt und auf wR = 0,038 (2113 Reflexe) bzw. 0,039 (257 Reflexe) verfeinert. Die Strukturen leiten sich vom orthorhombischen (GdFeO3-) bzw. kubischen Perowskit-Typ durch Jahn-Teller-Verzerrung ab. Die in beiden Verbindungen unterschiedlich gestreckten CuF64--Oktaeder (Mittelwert NaCuF3: Cu—F = 188,9/197,3/225,6(2) pm; RbCuF3: 188,3/197,8/237,6(3) pm) sind nach demselben Muster antiferrodistortiv geordnet, jedoch unter Winkelung Cu—F—Cu = 144,2…148,0(1)° in NaCuF3. Strukturelle Beziehungen zu den genannten Prototypen und zu vergleichbar Jahn-Teller-verzerrten Kupfer-Fluorverbindungen werden diskutiert.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 600 (1991), S. 239-248 
    ISSN: 0044-2313
    Keywords: Cyano-elpasolites ; bis(-tetramethylammonium) alkali hexacyanometallates ; preparation ; crystal structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tetragonal Cyano-Elpasolites: The Crystal Structures of [N(CH3)4]2KMn(CN)6 and [N(CH3)4]2RbCo(CN)6The tetragonal bis(-tetramethylammonium)-alkali-hexacyanometallates [N(CH3)4]2KMn(CN)6 (a = 884.8(2), c = 1222.2(6) pm) and [N(CH3)4]2RbCo(CN)6 (a = 884.7(1), c = 1233.1(2) pm) were prepared in the form of single crystals and their structures determined by X-ray methods (wR = 0.050 and 0.047 for 486 and 463 independent reflections, respectively; space group 14/m, Z = 2). The average distances in the resulting elpasolite structure, which is but slightly tetragonally distorted by small ferro-rotative displacements of the [M(CN6]3-) octahedra (Mn—C = 201.8, C—N = 115.6, K—N = 307.1 pm resp. Co—C = 190.7, C—N = 114.8, Rb—N = 320.1 pm), seem a bit enlarged if compared to related cyano complexes. Reasons for this are discussed using a tolerance factor concept for cyanoepasolites.
    Notes: Die tetragonalen Bis(-tetramethylammonium)-Alkali-Hexacyanometallate [N(CH3)4]2KMn(CN)6 (a = 884.8(2), c = 1222,2(6) pm) und [N(CH3)4]2RbCo(CN)6 (a = 884,7(1), c = 1233,1(2) pm) wurden in Form von Einkristallen dargestellt und röntgenographisch ihre Strukturen bestimmt (wR = 0,050 bzw. 0,047 für 486 bzw. 463 unabhängige Reflexe; Raumgruppe 14/m, Z = 2). Die mittleren Abstände in der resultierenden Elpasolithstruktur, die durch geringe ferrorotative Drehung der [M(CN)6]3--Oktaeder nur wenig tetragonal verzerrt ist (Mn—C = 201,8, C—N = 115,6, K—N = 307,1 pm bzw. Co—C = 190,7, C—N = 114,8, Rb—N = 320,1 pm), erscheinen leicht vergrößert im Vergleich zu Werten die in verwandten Cyanokomplexen beobachtet wurden. Gründe dafür werden im Rahmen einer Toleranzfaktorbetrachtung für Cyano-Elpasolithe diskutiert.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 610 (1992), S. 67-74 
    ISSN: 0044-2313
    Keywords: Copper weberites, Na2CuGaF7, Na2CuInF7 ; crystal structure ; magnetic investigation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Kupferweberite: Kristallstruktur und magnetische Untersuchung von Na2CuGaF7 und Na2CuInF7Die Kristallstruktur von zwei neuen Kupferweberiten Na2CuGaF7 und Na2CuInF7 wurde bestimmt. Na2CuGaF7: monokline Raumgruppe C2/c; a = 1232,5(5), b = 731,8(1), c = 1278,0(5) pm, β = 109,29(2)°, Z = 8. Na2CuInF7: orthorhombische Raumgruppe Pmnb; a = 731,8(1) pm, b = 1060,2(2) pm, c = 771,2(1) pm Z = 4. Die Strukturen wurden verfeinert mit 1175 Reflexen bis zu R = 0,043 (wR = 0,035) für Na2CuGaF7 und mit 1917 Reflexen bis zu R = 0,034 (wR = 0,025) für Na2CuInF7. Die Strukturen bestehen aus [CuF5]n3n--Ketten, die im Na2CuInF7 parallel zur a-Achse orientiert sind und in zwei alternierenden Richtungen im Na2CuGaF7. Die Natriumatome besitzen entweder siebenfache oder achtfache Koordination. Obwohl starke antiferromagnetische Wechselwirkungen innerhalb der Ketten beobachtet werden, gibt es keine Hinweise auf eine dreidimensionale Ordnung.
    Notes: The crystal structures of two new copper weberites Na2CuGaF7 and Na2CuInF7 have been determined. Na2CuGaF7 has the monoclinic space group C2/c: a = 1232.5(5) pm, b = 731.8(1) pm, c = 1278.0(5) pm, β = 109.29(2)° and Z = 8. Na2CuInF7 crystallizes in the orthorhombic space group Pmnb: a = 731.8(1) pm, b = 1060.2(2) pm, c = 771.2(1) pm and Z = 4. The structures have been refined from 1175 reflections to R = 0.043 (wR = 0.035) for Na2CuGaF7, and from 1917 reflections to R = 0.034 (wR = 0.025) for Na2CuInF7. The structures consist of [CuF5]n3n- chains which are parallel the a-axis in Na2CuInF7 and oriented in two alternating directions in Na2CuGaF7. Sodium atoms exhibit either seven-fold or eight-fold coordination. Although strong antiferromagnetic interactions are observed inside the chains, there is no evidence for three-dimensional ordering.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1686-1691 
    ISSN: 0044-2313
    Keywords: Sodium scandium fluoride ; cryolite structure ; tolerance factor ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Cryolite Structure of Na3ScF6 and the Tilting of Octahedra in Isostructural Sodium Hexafluorometallates Na3MF6X-ray studies at single crystals of Na3ScF6 confirmed the monoclinic cryolite type structure of this compound: a = 559.5, b = 580.2, c = 811.6 pm, β = 90.72°, Z = 2, space group P21/n; R1 = 0.021 for 512 symmetry independent reflections. The octahedra of [ScF6] (average Sc—F = 200.7 pm), as well as those of [NaF6] (Na1—F = 229.1 pm) linked to them, are titled by about 20° with respect to the axes of the perovskite-like pseudocell. This tilting of octahedra is discussed in comparison with other cryolites and with orthorhombic perovskites NaMF3; there results a correlation between tilt angle and tolerance factor t ˜ 0.88 of these compounds, the [NaF8] coordination of which invariably exhibits a constant mean value of Na2—F = 231.5 ± 1 pm for the four shortest distances.
    Notes: Eine röntgenographische Untersuchung an Einkristallen von Na3ScF6 bestätigte die monokline Kryolithstruktur dieser Verbindung: a = 559,5, b = 580,2, c = 811,6 pm, β = 90,72°, Z = 2, Raumgruppe P21/n; R1 = 0,021 für 512 symmetrie-unabhängige Reflexe. Die [ScF6]-Oktaeder (Mittelwert Sc—F = 200,7 pm) sind ebenso wie die mit ihnen verknüpften [NaF6]-Oktaeder (Na1—F = 229,1 pm) um etwa 20° gegen die Richtungen der perowskitartigen Pseudozelle gekippt. Diese Oktaederkippung wird im Vergleich mit anderen Kryolithen und mit den orthorhombischen Perowskiten NaMF3 diskutiert; dabei ergibt sich ein Zusammenhang zwischen Kippungswinkel und Toleranzfaktor t 〈 0,88 für diese Verbindungen, in deren [NaF8]-Koordination sich einheitlich ein konstanter Mittelwert von Na2—F = 231,5 ± 1 pm für die vier kürzesten Abstände zeigt.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1692-1697 
    ISSN: 0044-2313
    Keywords: Sodium copper scandium fluoride ; sodium zinc aluminium fluoride ; weberite structure ; crystal structure determination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structures of the Weberites Na2CuScF7 and Na2ZnAlF7At single crystals of the orthorhombic weberites Na2CuScF7 (Pmnb, Z = 4) and Na2ZnAlF7 (Imma, Z = 4) X-ray structure determinations were performed. Na2CuScF7 (Na2ZnAlF7): a = 726.0 (709.2), b = 1053.4 (1009.2), c = 765.8 (733.7) pm; R1 = 0.030 (0.042) for 887 (363) observed and independent reflections. The resulting average distances of the octahedrally coordinated metal atoms are: Cu—F = 200.7 pm, Sc—F = 201.7 pm; Zn—F = 198.8 pm, Al—F = 180.1 pm. Some structural relations and the variation in the bridge angles of the corner-sharing octahedra are discussed.
    Notes: An Einkristallen der orthorhombischen Weberite Na2CuScF7 (Pmnb, Z = 4) und Na2ZnAlF7 (Imma, Z = 4) wurden röntgenographische Strukturbestimmungen durchgeführt. Na2CuScF7 (Na2ZnAlF7): a = 726,0 (709,2), b = 1053,4 (1009,2), c = 765,8 (733,7) pm; R1 = 0,030 (0,042) für 887 (363) beobachtete und unabhängige Reflexe. Die resultierenden mittleren Abstände für die oktaedrisch koordinierten Metallatome sind: Cu—F = 200,7 pm, Sc—F = 201,7 pm; Zn—F = 198,8 pm, Al—F = 180,1 pm. Die Stukturverhältnisse und die Unterschiede in den Brückenwinkeln der eckenverknüpften Oktaeder werden diskutiert.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 595 (1991), S. 139-149 
    ISSN: 0044-2313
    Keywords: Cesium copper(II) fluoride, CsCu2F5 ; crystal structure ; magnetism ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structure of Cesium-containing Fluorides. IX. CsCu2F5, a Compound exhibiting Coordination Numbers 4, 5, and 6 for Copper(II)Single crystals of the monoclinic compound CsCu2F5 (a = 713.5, b = 738.6, c = 950.2 pm, β = 97.19°; P21/n, Z = 4) were prepared and their structure determined by X-ray methods (wR = 0.045 for 2140 independent reflections). Besides of square planar and elongated octahedral [CuFn] units (average Cu—F = 190.3 resp. 195.0/221.9 pm), the structure exhibits the first example of [CuF5] coordination, which is a distorted square pyramide (Cu—F = 190.7/221.6 pm). Relations to the pyrochlore structure are discussed, as well as the linking of polyhedra and the bridge angles Cu—F—Cu in context with the antiferromagnetic properties (TN = 54 K), which were found by powder susceptibility measurements.
    Notes: Einkristalle der monoklinen Verbindung CsCu2F5 (a = 713,5, b = 738,6, c = 950,2 pm, β = 97,19°; P21/n, Z = 4) wurden dargestellt und ihre Struktur röntgenographisch bestimmt (wR = 0,045 für 2140 unabhängige Reflexe). Neben quadratisch planaren und gestreckt oktaedrischen [CuFn]-Baugruppen (Mittelwerte Cu—F = 190,3 bzw. 195,0/221,9 pm) zeigt die Struktur das erste Beispiel einer [CuF5]-Koordination in Form einer verzerrten quadratischen Pyramide (Cu—F = 190,7/221,6 pm). Beziehungen zur Pyrochlorstruktur werden diskutiert, sowie die Vernetzung der Polyeder und die Brückenwinkel Cu—F—Cu im Zusammenhang mit den antiferromagnetischen Eigenschaften (TN = 54 K), die durch Suszeptibilitätsmessungen an Pulvern ermittelt wurden.
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  • 10
    ISSN: 0044-2313
    Keywords: Sodium trifluorometallates ; fluoroperovskites ; crystal structure ; tolerance factor ; antiferromagnetism ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal Structure Refinements of Sodium Trifluorometallates NaMF3 (M = Mg, Co, Ni, Zn): Tilting of Octahedra and Tolerance Factor of Orthorhombic FluoroperovskitesBased on newly measured X-ray single crystal data the crystal structures of the orthorhombic fluoroperovskites NaMF3 (M = Mg, Co, Ni, Zn) were refined in space group Pbnm (GdFeO3 type, Z = 4). The octahedra are but slightly distorted; the average distances (and bridge angles M—F—M) are: Mg—F = 197.8 pm (150.9°), Co—F = 203.8 pm (146.1°), Ni—F = 200.3 pm (148.0°) and Zn—F = 202.3 pm (147.4°). With respect to the axes of the pseudocell (Z = 1) the octahedra are rotated by tilt angles which vary, including NaMnF3 and NaFeF3, between 14.6 and 18.8°. The tilting becomes the more pronounced, the smaller the tolerance factor of the compound, so as to yield uniformly average values of Na—F = 232 pm for the four shortest distances within the [NaF8] coordination (distorted tetrahedron and bicapped trigonal prism, respectively). Measurements of magnetic powder susceptibilities show that tilting of octahedra is no sufficient cause to produce spin canting resulting in ferromagnetism: This property is confirmed only for NaNiF3 (TN = 150 K), whereas NaCoF3 exhibits a sharp minimum in its χ-l-T curve (TN = 75 K) and remains uncanted antiferromagnetic then down to 4.2 K.
    Notes: Auf der Basis neu gemessener röntgenographischer Einkristalldaten wurden die Kristallstrukturen der orthorhombischen Fluorperowskite NaMF3 (M = Mg, Co, Ni, Zn) in der Raumgruppe Pbnm verfeinert (GdFeO3-Typ, Z = 4). Die Oktaeder sind kaum verzerrt; die mittleren Abstände (und Brückenwinkel M—F—M) betragen: Mg—F = 197,8 pm (150,9°), Co—F = 203,8 pm (146,1°), Ni—F = 200,3 pm (148,0°) und Zn—F = 202,3 pm (147,4°). Unter Einbeziehung von NaMnF3 und NaFeF3 ergeben sich von 14,6 bis 18,8° variierende Kippungswinkel der Oktaeder gegen die Achsen der Pseudozelle (Z = 1). Die Oktaeder sind um so stärker gekippt, je kleiner der Toleranzfaktor der Verbindungen ist, so daß einheitlich ein Mittelwert von Na—F = 232 pm für die vier kürzesten Abstände innerhalb der [NaF8]-Koordination resultiert (verzerrtes Tetraeder bzw. zweifach überkapptes trigonales Prisma). Messungen der magnetischen Pulversuszeptibilität zeigen, daß die Oktaederkippung kein ausreichender Grund für Spinverkantung und daraus resultierenden Ferromagnetismus ist: Dieser kann nur für NaNiF3 (TN = 150 K) bestätigt werden, während NaCoF3 ein scharfes Minimum in der χ-1-T-Kurve zeigt (TN = 75 K) und dann bis herab zu 4,2 K unverkantet antiferromagnetisch bleibt.
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