Zur Kenntnis von K4PbO4 und Rb4PbO4

On K₄PbO₄ and Rb₄PbO₄ For the first time single crystals of K₄[PbO₄] have been prepared by heating K₄PbO₃ in O₂. The structure has been refined [K₄[PbO₄]: 3029 I₀(hkl), four circle diffractometer PW 1100, ω-scan, MoKα, R = 6.73%, R_w = 6.64%, P1 ; a = 658.62(15), b = 658.41(12), c = 986.64(21) pm, α = 79.74(2)°, β = 108.45(2)°, γ = 112.49(2)°, d_x = 3.79 g · cm^?3, d_pyk = 3.78 g · cm^?3, Z = 2; Rb₄[PbO₄]: a = 686.94(18), b = 684.43(18), c = 1020.73(21) pm, α = 79.28(2)°, β = 108.40(2)°, γ = 113.02(2)°, d_x = 4.87 g · cm^?3, d_pyk = 4.85 g · cm^?3, Z = 2, (from Rb₂PbO₃ and Rb₂O)]. Both compounds are isotypic with K₄SnO₄. The Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.     

Unerwartete Strukturverwandtschaft: Das neue Orthotitanat Rb3Na[TiO4]

On Unexpected Structural Relations: The New Orthotitanate Rb₃Na[TiO₄] [1] The new oxide Rb₃Na[TiO₄], platelike colourless crystals, was obtained by heating a well grounded mixture of the binary oxides in Ni-tubes. Therewith the oxides RbO_0.52, NaO_1.03, Ti₂O₃ (Rb:Na:Ti = 2.8:2.5:1.0) were heated for 26 d at 1000°C. Rb₃Na[TiO₄] (monoclinic, P2₁/c) is “isostructural” with Rb₃Na[PbO₄] [2] (lattice constants: a = 1076.3(3) pm, b = 638.8(4) pm, c = 1088.9(7) pm, β = 112.83(12)°; four-circle diffractometer data, Z = 4). The structure was determinated by using four-circle diffractometer data (Siemens AED2, 6683 I₀(hkl), MoKα , R = 6.2%, R_w = 3.8%, additional data see text). The Madelung Part of Lattice Energy (MAPLE), Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR) and the Charge Distribution in Solids are calculated and discussed.     

Zur Konstitution von ‚KPbO2’︁

On the Constitution of ‘KPbO₂’ Transparent, orangered single crystals of K₂Pb₂O₄ have been obtained by heating mixtures of K₂O₂ and PbO (K:Pb = 1:1) [Ag-cylinders, 560°C, 40 d, after cooling (15°C/h)]. The space group is P1 , a = 1295.94(9), b = 753.35(7), c = 697.12(8) pm, α = 118.00(1)°, β = 106.15(1)°, γ = 93.44(1)°, Z = 4, d_x = 6.573 und d_pyk = 6.54 g · cm³. The structure is characterized by rutilanalogous chains of edge-connected [PbO₆] octahedra along [001] according to [PbO_4/2O_2/1] = PbO₄. On both sides of such a chain there are respectively three O^2?, which belong to two octahedra, alternating capped with Pb²⁺ or not capped, corresponding to [PbO₄]Pb₂[PbO₄]□₂… = Pb₂O₄. Those capped chains are held together by K(1)…K(4), each of them with C.N. 6. The order of the chains corresponds to the motive of a closest packing. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Das erste gemischtvalente Oxoplumbat mit „isolierten”︁ Baugruppen: KNa7[PbIVO4][PbIIO3]

The First Mixed-valent Oxoplumbate with Isolated Anions. On KNa₇[Pb^IVO₄][Pb^IIO₃] For the first time KNa₇Pb₂O₇ has been prepared by reaction of K and Na Oxides with ?PbO₂”? rsp. PbO_red [e. g.: KO_0.48:NaO_0.36:?PbO₂”? = 1:7:2 (Ag-cylinders, reduced Ar-pressure, sealed in supremax-glas ampoules, 600°C, 14 d): redorange single crystals of plated shape]. The structure determination [3269 I_o(hkl), four-circle diffractometer PW 1100 (Fa. Philips), ω-scan, MoKα, R = 9.52%, R_w = 7.67%, absorption not considered] proves the space group P2₁/c with a = 1758.48(10), b = 596.76(3), c = 1066.46(8) pm, β = 90.682(8)°, Z = 4, d_x = 4.311, d_pyk = 4.28 g/cm³. The structure is characterized by isolated [Pb^IVO₄] (symmetry nearly T_d) and [Pb^IIO₃] groups (symmetry nearly C_3v), the latter connected by cations to double-layers. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Na4[PbO4] — Darstellung neuer Plumbate(IV) durch Oxydation intermetallischer Phasen

Na₄[PbO₄] — Preparation of new Plumbates(IV) by Oxidizing Intermetallic Phases By oxidizing NaPb with Na₂O₂ (molar ratio Na₂O₂:NaPb = 2.04:1; Ag-tubes; 600°C/50d) we obtained for the first time small orange coloured single crystals of Na₄[PbO₄]: Na₄[SiO₄]-type [2], P? 1 (I.T. No. 2) with a = 898.5(3); b = 675.6(3); c = 592.2(2) pm; α = 124.75(1)°; β = 96.75(1)°; γ = 100.18(2)°; Z = 2; (four circle diffractometer data (MoK; 3 251 I_o(hkl); R = 3.4%; R_w = 3.0%), parameters see text. Furthermore the Madelung part of lattice energy (MAPLE), effective coordination numbers (ECoN), mean fictive ionic radii (MEFIR) and the charge distribution (CHARDI) are being calculated.     

Über quaternäre Oxoplumbate(IV). Zur Kenntnis von Rb2Li14[Pb3O14] und Cs2Li14[Pb3O14]

On Quaternary Oxoplumbates(IV). On the Knowledge of Rb₂Li₁₄[Pb₃O₁₄] and Cs₂Li₁₄[Pb₃O₁₄] For the first time, Rb₂Li₁₄[Pb₃O₁₄] and Cs₂Li₁₄[Pb₃O₁₄] have been prepared by heating of mixtures of Li₂O, β-?PbO₂”? and Rb₂PbO₃, Cs₂PbO₃ respectively with Li:Pb:A = 14:3:2, (A = Rb, Cs). [Ag-cylinders, sealed under vacuum in Duran-glass ampoule, 590 and 550°C, 40 d, powder (650°C, 200 d, single crystals of Rb₂Li₁₄[Pb₃O₁₄])]. Rb₂Li₁₄[Pb₃O₁₄] is nearly colourless with ivory nuance, Cs₂Li₁₄[Pb₃O₁₄] is pale yellow. According to powder and single crystal investigations, both are isotypic with K₂Li₁₄[Pb₃O₁₄]. Structure refinement of Rb₂Li₁₄[Pb₃O₁₄]: 1015 symmetry independent reflexions, four-circle-diffraktometer PW 1100 (Fa. Philips), ω-scan, MoKα, R = 5.73%, R_W = 5.33%, absorption not considered, space group Immm with a = 1284.71(9), b = 793.90(4), c = 727,35(5) pm, d_x-ray = 4.99 g · cm^?3, d_pyc = 5.01 g · cm^?3, Z = 2. Cs₂Li₁₄[Pb₃O₁₄]: a = 1295.28(12), b = 796.69(8), c = 732.44(7) pm, d_x-ray = 5.31 g · cm^?3, d_pyc = 5.28 g · cm^?3, Z = 2. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.     

Thio- und Selenomercurate(II). K6[HgS4], K6[HgSe4], Rb6[HgS4] und Rb6[HgSe4]

Thio- and Selenomercurates(II). K₆[HgS₄], K₆[HgSe₄], Rb₆[HgS₄] and Rb₆[HgSe₄] We prepared by annealing intimate mixture of pure samples of K₂S, K₂Se, Rb₂S, and Rb₂Se with HgS or HgSe [360–380°C, 7d, Duran-glass-seal with Argon] with hexagonal Na₆ZnO₄ isotypic new mercurates: K₆[HgS₄] [bright citronic yellow a = 9.98₅, c = 7.65₂ Å], K₆[HgSe₄] [light orange yellow a = 10.3₆, c = 7.88₃ Å], Rb₆[HgS₄] [bright yellow a = 10.3₄, c = 7.94₂ Å], Rb₆[HgSe₄] [orange-red a = 10.7₂, c = 8.19₂ Å]. The crystal structure of K₆ Hgs₄ is elucidated by using diffractometer data of single crystals: P63mc, C⁴_6v, it is R = 6.6% for 304 reflexes [h k o–h k 4, anisotropic refinement MoKα]; for position and parameters see text d_rö = 2.83₅, d_pyk = 2.99 g · cm^?3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.     

Über quaternäre Oxowolframate (VI) Na6Li2[W2O10] - ein Diwolframat

On Quaternary Oxotungstates (VI). Na₆Li₂[W₂O₁₀] — a Ditungstate For the first time, Na₆Li₂[W₂O₁₀] has been prepared by annealing mixtures of WO₃, Na₂O and Li₂O with W:Na:Li = 1:3:1 [closed Pt-tube in quartz-glass ampoule, 840°C, 60 d (single crystals)]. The colourless crystals are of squatted shape. The structure determination [1813/I₀(h kl), four-cycle diffractometer PW 1100 (Fa. Philips), ω-scan, AgK_α, R = 8.32%, absorption not considered] confirms the space group P1 with a = 784.66(11), b = 602.53(7) c, = 563.81(11) pm α = 106.784(14)°, β = 114.548(14)°, γ = 91.082(13)°, Z = 2, d_x = 4.92 g · cm^?3, d^pyk = 4.85 g · cm^?3. The structure may be described as a distorted derivative of the NaCl-type. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed.     

Zur Kenntnis von Na4[CrO4]

On Na₄(CrO₄) Dark-green single crystals of Na₄[CrO₄] were obtained for the first time. (Na₂O/Cr₂O₃; Na:Cr = 4:1 not exactly closed Ni-tube; 1000°C; 30 d). It is isostructural to Na₄(CoO₄); space group P1 , a = 859.7 pm, b = 569.8 pm, c = 640 pm, α = 124°C, β = 98.4°, γ = 98.9°, Z = 2. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.     

Synthese,Kristallstrukturen und Absorptionsspektren der neuen „Cupriosilicate”︁: K6[CuSi2O8] und Rb4[CuSi2O7]

Synthesis, Crystal Structures, and Absorption Spectra of the New “Cupriosilicates”: K₆[CuSi₂O₈] and Rb₄[CuSi₂O₇] K₆[CuSi₂O₈] and Rb₄[CuSi₂O₇] were obtained by annealing intimate mixtures of K₂O and Rb₂O, respectively, CuO and SiO₂ in sealed Ag cylinders at 500°C as transparent greenish-blue single crystals. The structure solution (IPDS-data Mo Kα; K₆[CuSi₂O₈]: 1292 F²(hkl), R1 = 0.059; wR2 = 0.103 and Rb₄[CuSi₂O₇]: 763 F²(hkl), R1 = 0.049; wR2 = 0.114) confirms the space group P1 for both compounds. K₆[CuSi₂O₈]: a = 619.4(2); b = 665.5(2); c = 753.0(2) pm; α = 83.66(3); β = 87.71(3); γ = 70.19(3)°; Z = 1. Rb₄[CuSi₂O₇]: a = 631.9(9); b = 707.5(10); c = 715.2(6) pm; α = 114.2(1); β = 100.7(1); γ = 107.9(1)°; Z = 1. The Madelung Part of the Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these calculated via Mean Effective Ionic Radii, MEFIR, are given. The absorption spectra of K₆[CuSi₂O₈] and Rb₄[CuSi₂O₇] are discussed in terms of the Angular Overlap Model, AOM.     

Rb7[SiO4][VO4]: ein Ortho‐Silicat‐Vanadat(V)

Rb₇[SiO₄][VO₄]: an Ortho‐Silicate‐Vanadate(V) Rb₇[SiO₄][VO₄] has been obtained from a redox reaction between CdO and vanadium metal in the presence of Rb₂O and SiO₂ at 600 °C in an Ag container as yellow‐greenish transparent single crystals. The crystal structure determination (IPDS data: P2₁/c, a = 637.6(1) pm, b = 1039.7(1) pm, c = 2076.8(4) pm, β = 93.21(2)°, Z = 4, wR2 = 0.1319) reveals the presence of isolated complex anions, [SiO₄]^4— and [VO₄]^3—.     

“Fragmentierung” und “Aggregation” bei Bleioxiden Über das Oligooxoplumbat(IV) K2Li6[Pb2O8]

“Fragmentation” and “Aggregation” on Lead Oxides. On the Oligooxoplumbate(IV) K₂Li₆[Pb₂O₈] For the first time, the dinuclear Oxoplumbate(IV) K₂Li₆[Pb₂O₈] has been prepared as transparent colourless single crystals by heating mixtures of K₂PbO₃, Li₂O, and “PbO₂” with K:Li:Pb = 1:3:1 e. g. [Ag-cylinders, sealed under vacuum in Supremax-glass ampoule, 660°C, 120 d]. The structure determination verifies the space group P1 with a = 6.9720(9), b = 5.9252(6), c = 5.9312(7) Å, α = 88.05(1)°, β = 107.94(1)°, γ = 107.30(1)°; d_x = 4.95 g · cm^?3, d_pyk = 4.91 g · cm^?3; Z = 1, [2107 symmetry independent hkl, fourcircle-diffractometer Philips PW 1100, ω—2Θ—scan, MoKα, R = 5.07%, R_w = 4.59%, absorption not considered]. The structure is characterized by the group [Pb₂O₈] — two edge connected (equatorial/apical) trigonal bipyramids — that is observed for the first time. Several ways of synthesis are given. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Effective Ionic Radii, MEFIR, are calculated.     

Die ersten Oxocobaltate(II) mit zweikernigem Anion: Rb2Na4[Co2O5] und K2Na4[Co2O5]

The First Oxocobaltate(II) with Dinuclear Anion: Rb₂Na₄[Co₂O₅] and K₂Na₄[Co₂O₅] By heating of well ground mixtures of the binary oxides [A₂O, Na₂O, ?CoO”?, A:Na:Co = 1.00:2.00:1, (A = K, Rb); Ag-tube, 600°C, 14 d] we obtained Rb₂Na₄[Co₂O₅] and K₂Na₄[Co₂O₅] rough, transparent, red single crystals. We find a new type of structure with the anion [O₂CoOCoO₂]^6?. Space group P4₂/mnm; a = 634.4 pm, c = 1030.3 pm, Z = 2 (A = K) a = 647.6 pm, c = 1021.1 pm, Z = 2 (A = Rb); four-circle diffractometer data; MoKα -radiation; 360 from 364 I₀(hkl), R = 4.34%, R_w = 3.54% (A = K); 361 from 366 I₀(hkl), R = 6.54%, R_w = 2.70% (A = Rb). The anion is planar, the CN of Co is 3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed.     

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 des Rb2PbO3-Typs: Über Rb2ZrO3, Rb2SnO3 und Rb2TbO3

According to X-ray powder work, orthorhombic Rb₂ZrO₃ [a = 10.7, b = 7.40, c = 5.87 Å] and Rb₂SnO₃ [a = 10.7, b = 7.49, c = 5.75 Å] are isotypic with Rb₂PbO₃. Discussion of different structural models and the Madelung Part of Lattice Energy (MAPLE) shows that the annormal Coordination Number of M⁴⁺ (CN = 5) is caused by the type of formula.     

Zur Kristallstruktur von Li8PbO6 [1]

On the Structure of Li₈PbO₆ For the first time single crystals of Li₈PbO₆ have been prepared by heating of mixtures of Na₂PbO₃ and Li₂O [Ag-cylinders, 650°C, 150 d]. The structure [382 I₀(hkl), four circle diffractometer PW 1100, ω/2Θ-scan, MoKα, R = 3.07%, R_w = 3.00%, space group R3 ; a = 555.09(4), c = 1564.13(17) pm, D_x = 4.28 g · cm^?3, D_pyk = 4.24 g · cm^?3, Z = 3] is characterized by the motive of a hexagonal-closed O^2? packing. Half of the octahedral sites are occupied by Pb⁴⁺ and Li⁺ and half of the tetrahedral sites only by Li⁺. The Madelung Part of Lattice Energy, MAPLE, and the Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated.     

Über Oxotitanate der Alkalimetalle. Zur Kenntnis von Na4Ti5O12

On Oxotitanates of the Alkaline Metals: On Na₄Ti₅O₁₂ Colourless single crystals of the new titanate Na₄Ti₅O₁₂ (starting from mixtures Na₂O/TiO₂, 1000°C, 6 d, Au-crucible, open system) crystallize in the monoclinic system, space group C2/m, a = 26.544(9), b = 2.952(1), c = 6.322(3) Å, β = 95.79(3)°, Z = 2, d_rö = 3.45 and d_pyk = 3.38 g · cm^?3 (four-cycle-diffractometer data, PW 1100, 2?-scan, MoKα). R = 5.09% and R_w = 4.87% for 1178 independent I₀(hkl) with 3° ≤ 2? ≤ 34°. Corrugated layers of Ti₅O₁₂, held together by Na⁺, are stacked along [001]. Details about partially occupied positions of Na⁺, Effective Coordination Numbers (ECoN), the Madelung part of lattice energy (MAPLE), and the structural differences to Na₂Ti₃O₇ are discussed.     

Ein neues Oxoberyllat: K2Na4[O2BeOBeO2]

On K₂Na₄[O₂BeOBeO₂] For the first time colourless single crystals of K₂Na₄[Be₂O₅] which are isotypic with K₂Na₄[Co₂O₅] [2] and Rb₂Na₄[Co₂O₅] have been prepared by heating e.g. a well ground mixture of K₂O, Na₂O and BeO (K:Na:Be = 2.2:4.4:2; 750°C; 21 d; Ni-tube). The crystal structure was solved by four-circle diffractometer data [Siemens AED 2; 389 I_o(hkl); space group P4₂/mnm; Z = 2; a = 595.17(4) pm, c = 1 002.66(9) pm; R = 4.1%; R_w = 2.3%]. Mean Fictive Ionic Radii, MEFIR, Effective Coordination Numbers, ECoN, the Madelung Part of Lattice Energy, MAPLE, and the charge distribution are calculated.     

Zur Kenntnis von Unordnungsphänomenen bei Oxiden mit dem „Schmetterlingsmotiv”︁ Über Rb2K4[O2CoOCoO2]

On the Knowledge of Disorder Phenomena in Oxides with the Motive of Butterfly. On Rb₂K₄[O₂CoOCoO₂] For the first time Rb₂K₄Co₂O₅ was obtained by annealing intimate mixtures of the binary oxides as dark red single crystals (Rb:K:Co = 1.2:3.2:1; Ni-tube; 570°C; 20 d). Structure Refinement [fourcircle diffractometer data; PW 1100; AgK radiation; 401 of 607 I₀(hkl); R = 9.9%; R_w = 5.5%; space group P4₂/mnm; Z = 2; a = 674,2(4), c = 1172,2(6) pm] confirms the isotypism to K₂Na₄Co₂O₅, Rb₂Na₄Co₂O₅ [2] and K₂Na₄Be₂O₅ [3]. The Madelung Part of Lattice Energy, MAPLE, Effektive Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, and the Charge Distribution, ΣQ, were calculated. The isotypism of Rb₂K₄Co₂O₅ and Rb₂Na₄Co₂O₅ is compared graphically.     

Über „Lithovanadate”︁: Zur Kenntnis von Rb2[LiVO4] und Cs2[LiVO4]

On ?Lithovanadates”?: Rb₂[LiVO₄] and Cs₂[LiVO₄] By heating of well ground mixtures of the binary oxides [A₂O, Li₂O, V₂O₅, A : Li: V = 2.2 : 1.1 : 1.0 (A = Rb, Cs); Ni-tube, 750° 25 d] we obtained Rb₂[LiVO₄] and Cs₂[LiVO₄] colourless, orthorhombic single crystals. We found a new type of ?Lithovanadate”?-structure: space group Cmc2₁; a = 587.9(1), b = 1170.1(1), c = 793.3(1) pm, Z = 4 (A = Rb) bzw. a = 610.5(1), b = 1222.6(3), c = 815.5(2) pm, Z = 4 (A = Cs). The structure was determined by four-circle diffractometer data [MoKα -radiation; 997 from 1157 I₀(hkl), R = 7.75%, R_w = 5.54% (A = Rb); 686 from 686 I₀(hkl), R = 6.97%, R_w = 4.20% (A = Cs)] parameters see text. The Madelung part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated.