Über gemischtvalente Oxoplumbate. Zur Kenntnis von Rb2Pb4O7 = Rb2PbPbO7

On Mixed-valent Oxoplumbates. On Rb₂Pb₄O₇ = Rb₂Pb Pb O₇ For the first time, Rb₂Pb₄O₇ has been prepared by annealing mixtures of Rb₂O₃ and PbO with Rb:Pb = 1:2 [Ag-cylinders, sealed under vacuum in Duran-glass ampoule, 450°C, 30 d (single crystals)]. The rubin red single crystals are of longish [001] shape. The structure determination [5162 symmetry independent hkl, four-circle-diffractometer CAD 4 (Fa. Enraf-Nonius), ω-2Θ—scan, AgKα, ψ-scan absorption correction, R = 7.54%, R_W = 7.71%] confirms the space group P1 with a = 1036.00(10), b = 733.72(8), c = 663.54(10) pm, α = 90.049(12)°, β = 99.236(12)°, γ = 101.641(12)°, Z = 2, d_rö = 7,58 g · cm^?3, d_pyk = 7,55 g · cm^?3. The structure is characterized by a layer-lattice. The coordination number is three for Pb²⁺, six for Pb⁴⁺. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.     

Zur Kenntnis von Li2[CuO2] [1, 2]

On Li₂[CuO₂] At the first time single crystals of Li₂[CuO₂] are prepared by exchange reaction. The crystal structure (I mmm) with a = 365.4(0), b = 285.9(0), c = 937.4(0) pm, Z = 2, d_x = 3.73 g/cm³, d_pyk = 3.67 g/cm³ was refined (four-circle-diffractometer data PW 1100, 343 I_o(hkl), MoKα, R = 0.046, R_w = 0.041). The characteristic structure element is the planar chain \documentclass{article}\pagestyle{empty}\begin{document}$ {}_\infty ^1 \left[{{\rm CuO}_{4/2}} \right]^{2 -} $\end{document}. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.     

Oxide eines neuen Formeltyps: Zur Kenntnis von K3Ni2O4 und K3Pt2O4

Oxides of a New Type of Formula: On the Knowledge of K₃Ni₂O₄ and K₃Pt₂O₄ K₃Ni₃O₄, greyblack single crystals, obtained by heating K₂O and NaNiO₂ [K:Ni = 2:1, 500°C, 7d, Ag-cylinders], crystallizes orthorhombic with a = 6.04₄, b = 9.04₉, c = 10.56₇ Å, Z = 4, space group Cmcm (d_rö = 3.43, d_pyk = 3.32 g · cm^?3). Due to four cycle diffractometer data (374 hkl, MoKα, R = 8.6percnt;) a new type of structure is found with wavebands of [NiO_4/2] \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^{\rm 1} $\end{document} exhibits the C.N. 6, \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^{\rm 2} $\end{document} the C.N. 4. Effective Coordination Numbers, ECoN, calculated by means of Mean Fictive Ionic Radii, MEFIR, the Madelung Part of Lattice Energy, MAPLE and the magnetic properties are discussed. K₃Pt₂O₄, black single crystals with metallic lustre, obtained by heating KO_x (x = 1.55 or 1.88) and Pt (powder) [K:Pt = 4:1,1000°C, lh, 600°C, 2d, Pt-capsules] is isotypic to K₃Ni₂O₄ (four cycle diffractometer data: 458 hkl, MoKα, R = 12percnt;). Cellparameters are a = 6.15, b = 9.27, c = 11.51 Å (single crystal data), d_rö = 5.79 and d_pyk = 5.77 g · cm^?3.     

Neue Elpasolithvertreter mit CoIII: Cs2KCoF6, Rb2KCoF6, Rb2NaCoF6 (mit einer Notiz über Cs2NaCoF6)

New Elpasolithes with Co^III: Cs₂KCoF₆, Rb₂KCoF₆, Rb₂NaCoF₆ (with a Notice on Cs₂NaCoF₆) New prepared are the compounds Cs₂KCoF₆ (a = 8.97₉ Å), Rb₂KCoF₆ (a = 8.80₉ Å), Rb₂NaCoF₆ (a = 8.42₁ Å), all cubic Elpasolithes, as well as Cs₂NaCoF₆ (Cs₂NaCrF₆?type, hexagonal with a = 6.23, c = 30.32 Å) all of light blue colour. Cs₂KCoF₆ (72.7–299.7 K) and Rb₂KCoF₆ (71.4–298.0 K) have been measured magnetically. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.     

Neue Oxozincate der Alkalimetalle: Rb2[ZnO2] und Cs2[ZnO2]

New Oxozineates of Alkali Metals: Rb₂[ZnO₂] and Cs₂[ZnO₂] Colorless single crystals of the hitherto unknown Rb₂[ZnO₂] (a = 9.55₈, b = 6.33₅, c = 15.91 Å, β = 118.6°, z = 8, d_pyk = 4.11, d_rö = 4.21 g · cm^?3) and Cs₂[ZnO₂] (a = 9.85₁, b = 6.61₉, c = 16.26 Å, β = 116.8°) have been prepared, which crystallize monoclinic, P2₁/c – D. (For parameters see text.) Unexpected there are “isolated” groups [Zn₄O₈]. Half of the Zn atoms exhibit the unusual coordination number 3 towards O^2?. The Madelung Part of Lattice Energy, MAPLE, and the Effective Coordination Number, ECoN, the latter by means of Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Neue Oxogallate der Alkalimetalle: Über K6[Ga2O6] und Rb6[Ga2O6], sowie Na3GaO3 und Cs6[Ga2O6]

New Oxogallates of Alkaline Metals: On K₆[Ga₂O₆] and Rb₆[Ga₂O₆] as well as Na₃GaO₃ and Cs₆[Ga₂O₆] Due to powder and single crystal data K₆[Ga₂O₆] a = 7.09₉; b = 11.11₆; c = 6.48₄ Å; ß = 101.6₆° and Rb₆[Ga₂O₆] a = 7.39₃; b = 11.47₅; c = 6.79₈ Å; ß = 103.5° crystallize isotypic with K₆[Fe₂O₆]; space group C2/m-C₃^2h; As well has been prepared the hitherto unknown Na₃GaO₃ a = 11.48, b = 10.82, c = 6.13 Å, space-group Imcm or I2cm Z = 8; and Cs₆[Ga₂O₆] a = 7.2₆, b = 12.1, c = 7.6₈ Å, ß = 105°, Z = 4, space-group P2₁/a.     

Neue Oxoplumbate(II) A2PbO2 (A = K,Rb, Cs) mit zweikernigen Gruppen [OPbO2PbO]

New Oxoplumbates(II) A₂PbO₂ (A = K, Rb, Cs), with Binuclear Groups [OPbO₂PbO] Unknown K₂PbO₂, Rb₂PbO₂ and Cs₂PbO₂ (yellowish powder, yellowish transparent single crystals, respectively) have been prepared, The compounds crystallize triclinic with a = 10.90₁ Å, b = 7.60₆ Å, c = 7.32₈ Å, α = 119.3₅°, β = 88.4₂°, γ =117,7₃°, (K₂PbO₂); a = 10.90₇ Å, b = 8.51₀ Å, c = 7.81₅ Å, α = 124.0₀°, β = 84.9₇°, γ = 120.6₈° (Rb₂PbO₂) and a = 11.64₄ Å, b = 8.90₅ Å, c = 8.04₀ Å, α = 123.3₂°, β = 85.7₀°, γ = 120.4₉° Z = 4, space group P1 -C/_i¹. For K₂PbO₂ we find R = 8.6₅% and R_w = 9.3₂% (2283 independent reflections). Parameters see text. There are isolated [Pb₂O₄]groups, which are connected in a complicated way by mutual K⁺ ions forming layers. The Madelung Part of the Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these by means of mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Ein neues Oxogermanat: Li8GeO6 = Li8O2[GeO4]. (Mit einer Bemerkung über Li8SiO6 und Li4GeO4)

A New Oxogermanate: Li₈GeO₆ ? Li₈O[GeO₄] Transparent colourless single crystals of Li₈GeO₆(P6₃cm, a = 550.09(8), c = 1072.2(3) pm, Z = 2; 4-circle-diffractometer Siemens AED 2, MoKα; 326 I_o(hkl), R = 2.4%, R_w = 2.0%), have been prepared. As by-product we always got colourless isometric single crystals of Li₄GeO₄. For the first time we could grow single crystals of Li₈SiO₆ of suitable size and quality. Our structure refinement confirms the assumed structure model [2]: Li₈GeO₆ and Li₈SiO₆ are isotypic with Li₈CoO₆[3] (Li₈SiO₆: a = 542.43(8), c = 1062.6(2) pm, Z = 2; 4-circle-diffractometer Siemens AED 2, MoK_α; 306 I_o(hkl), R = 3.6%, R_w= 3.0%). The known crystal structure of Li₄GeO₄ [4] is confirmed and refined (Cmcm, a = 776.6(2), b = 735.7(3), c = 604.9(2) pm, Z = 4; 4-circle-diffractometer Siemens AED 2, MoKα, 298 I_o(hkl), R = 1.9%, R_w = 1.4%). The Madelung Part of Lattice Energy, MAPLE, and Effective coordination-Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.     

Zur Kenntnis ternärer Oxide des Bleis: Über Na2PbO2

On Ternary Oxides of Lead. The Na₆PbO₅ Na₆PbO₅ (pale yellow) crystallizes orthorhombic in Cmcm with a=10.6₈, b=5.70₉, c=10.9₉, å; Z=1. Parameters were refined by least-squares (479 hkO–hk7, MO–K_α) R=0.112₄, R′=0.116, (parameters see text). Isolated PbO₅ groups of pseudotetragonal pyramids lend Pb⁴⁺ Coordination Number (CN) 5. Along [100] and [010] the pyramids are equivalent orientated, but along [001] alternately twisted by 180°. Na+ occupies holes between O^2?, leading to CN 6 (Na″+) and Na″′⁺ and CN 4 (Na′⁺). The MADELUNG part of lattice energy (MAPLE) is calculated and discussed.