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31.
Novel meander with Co3+ und Au3+: Na4[AuCoO5] = Na8 1∞ [(O2/2 (CoO)O2AuO2/2)2] By “reaction with the wall” we obtained for the first time transparent brown single crystals of Na4[AuCoO5] while heating intimate mixtures of Co3O4, Na2O2, and K2O2 (Co: Na: K = 1.00:4.91:2.20; 650°C/44d) in a sealed gold-tube: monoclinic, P21/m, with a = 555.69(4) pm, b = 1042.11 (8) pm, c = 555.69(4) pm, β = 117.387(5)°, Z = 2. Characteristic features of Na4[AuCoO5] are meandric chains [(O2/2 (CoO)O2AuO2/2)2]. The structure has been determined by four-circle diffractometer data (Siemens AED 2; Mo? Kα , graphite, 881 I0(hkl), R = 0.0366, Rw = 0.0316), parameters as given in the text. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, these via Mean Fictive Ionic Radii, and Charge-distribution, CHARDI, are calculated and discussed. 相似文献
32.
33.
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%, Rw = 3.54% (A = K); 361 from 366 I0(hkl), R = 6.54%, Rw = 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. 相似文献
34.
New Metal Oxides with Doubles of Tetrahedra as Building Units: Rb6[Tl2O6] and Cs6[In2O6] We prepared the hitherto unknown Rb6[Tl2O6] and Cs6[In2O6] by heating mixtures of Tl2O3 and RbO0.60 (Rb:Tl = 3.5:1) as well as In2O3 and CsO0.53 (Cs:In = 3.5:1) as single crystals [closed Ag-cylinder, 650°C, 14 d]. The single crystals of Rb6[Tl2O6] are yellow, those of Cs6[In2O6] pale yellow, all transparent and rude. The new type of structure was elucidated by 4-circle-diffractometer (PW 1100) data. Rb6[Tl2O6]: P21/a; a = 1145,7(3), b = 713,3(1), c = 783,9(2) pm, β = 93,73° (2), Z = 2; Ag–Kα, 2100 out of 2531 I0(hkl), R = 9,6% and Rw = 8,9%. Cs6[In2O6]: P21/a; a = 1178,5(4), b = 730,7(2), c = 816,3(2) pm, β = 95,38° (3), Z = 2; Mo–Kα, 1584 out of 2032 I0(hkl), R = 9,25%, and Rw = 8,44%. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed. 相似文献
35.
About Perrhenates. 3 On the Structure of the Mesoperrhenate Na3[ReO5] By tempering powder samples (prepared from mixtures of binary oxides: Na2O2/ReO2 and Na2O/ReO3 respectively, Na : Re = 3 : 1, Ar and O2 atmosphere respectively, 400–450°C, corundum boat) in a closed Ag cylinder (500–550°C, 10 d) yellow single crystals of Na3ReO5, sensitive to moisture, were grown. The compound crystallizes trigonal, space group P31, P32 respectively, with a = 5.544(1), c = 13.580(7) Å, Z = 3, drö. = 4.62 g/cm3. The crystal structure [4-circle diffractometer data, 1091 I0(hkl), AgKα, R = 6.14, Rw = 6.08%] is characterized by “isolated” bipyramids ReO5. Na+ ions are occupying all the tetrahedral (Na2, Na3) and octahedral (Na1) holes of the pseudocubic face centred (c/a = 2.441) Re part of the lattice; resulting in a Na3Re kation framework corresponding to the Li3Bi type of structure. Effective Coordination Numbers (ECoN), the Madelung Part of Lattice energy (MAPLE) and the charge distribution (CHARDI) are computed and discussed. 相似文献
36.
On Tantalates and Niobates ‘rich in Cations’. On Na5TaO5 and Na5NbO5 Colourless, transparent single crystals of Na5TaO5 [annealed mixtures of Na2O, Li2O, and Ta2O5, Na : Li : Ta = 6.6 : 1.1 : 1, Ni-cylinder, 1000°C, 75 d] as well as Na5NbO5 [annealed mixtures of Na2O, Li2O, and Nb2O5, Na : Li : Nb = 6.6 : 1.1 : 1, Ni-cylinder, 1000°C, 75 d] have been prepared. Single crystal data show that both isotypic oxides represent a deformed variant of the NaCl-type of structure [Na5TaO5: 1154 from 1250 I0 (hkl), four-cycle diffractometer Philips PW 1100, ω2-θ scan, Ag? Kα , R = 4.88%, space group c2/c with a = 629.3(1) pm, b = 1025.4(2) pm, c = 1004.6(2) pm, b? 106.80(2)°, z = 4 and Na5NbO5: 998 from 1247 I0(hkl), four-cycle diffractometer Philips PW 1100, ω-2θ scan, Ag? Kα , R = 8.58% and Rw = 7.67%, space group C2/2 with a = 629.1(1) pm, b = 1024.4(2) pm, c = 1004.2(2) pm, b? = 106.80(2)°, Z = 4]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Fictive Ionic Radii, MEFIR, as well as Charge Distribution, CHARDI, are calculated. 相似文献
37.
The First Diniobate with ‘Isolated’ Anions: KLi4[NbO5]=K2Li8[Nb2O10] [1] . By heating of well ground mixtures of the binary oxides [K2O, Li2O, Nb2O5, K:Li:Nb=1.1:4.4:1, Pt-tube, 1100°C, 3d] colourless, triclinic single crystals of KLi4NbO5 have been prepared for the first time: space group P1 (Nr. 2) with a=816.9(2) pm, b=592.2(2) pm, c=589.7(2) pm, α=121.00(2)º, β=91.78(2)°, γ=99.23(2)°, Z=2. The crystal structure was solved by four-cycle diffractometer data [Mo-Kα , 1386 from 1386 Io(hkl), R=3.4%, Rw=2.6%], parameters see text. Characteristic for this structure are “isolated” groups of [Nb2O10] and the tetrahedral coordination of Li(1), Li(2), and Li(3). Li(4) has a tetragonal-pyramidal coordination. The structural relations are deduced by Schlegel Diagrams. The Madelung Part of Lattice Energy, MAPLE, the Effective Coordination Numbers, ECoN and the charge distribution have been calculated and discussed. 相似文献
38.
On Oxostannates(II). V. Na4[SnO3] – The First Oxostannate (II) with Island Structure The new oxid Na4SnO3 (yellow, transparant single crystals) has been prepared by heating of mixtures of: 1. NaO0.45 and SnO (Na:Sn2+ = 4.1:1; Ag-cylinders; 600–730°C, 7–66 d); 2. NaO0.45′ SnO2 and Sn±0 (Na:Sn4+:Sn±0 = 8.2:1:1; Ag-cylinders; 650–680°C, 2–66 d); 3. NaO0.45′ Na2SnO3 and Sn±0 (Na:Na2SnO3:Sn±0 = 6.1:1:1; Ag-cylinders; 650–670°C, 5 d). Na4SnO3:804 I0(hkl); four circle diffractometer PW 1100; ω-scan; MoKα; R = 5.14%; Rw = 4.64%; monoclin, Cc? C; a = 582.77(11), b = 1667.44(24), c = 589.42(10) pm, β = 110.187(13)°; dx = 3.20 g/cm3; dpyk = 3.19 g/cm3; Z = 4; parameter look for text. It is a NaCl-variant with systemathical blanks of the anion part and “isolated” groups of [SnO3]. \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm N}\mathop {\rm a}\limits^{\rm 1} $\end{document} has the uncommon coordination number 2. The Effective Coordination Numbers, ECoN, the Mean Fictive Ionic Radii, MEFIR, and the Madelung Part of Lattice Energy, MAPLE, are calculated. The structure is described using ?Erweiterte Schlegeldiagramme”?. 相似文献
39.
On Oxostannates(II). III. K2Sn203, Rb2Sn203, and Cs2Sn2O3 – a Comparison Hitherto unknown Rb2Sn2O3 has been obtained by heating of mixtures of binary oxides [RbO0.48 + SnO, Rb:Sn = 1.1:1, Al2O3?cylinders, Ar] as deep yellow powder or deep yellow single crystals. It is isotypic to K2Sn2O3, R3 m-D with a = 6.086 Å, c = 15.101 Å, Z = 3, dcalc = 4.69, dobs = 4.64 g X cm?3. For 260 hkl it is R = 5.27% and Rw = 5.09% (MoKα, 4-circle diffractometer data). The structure of K2Sn2O3 and Rb2Sn2O3 is compared with that of Cs2Sn2O3. For both types Effektive Coordination Numbers, ECoN, and the Madelung Part of Lattice Energy, MAPLE, have been calculated. 相似文献
40.
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%, RW = 5.33%, absorption not considered, space group Immm with a = 1284.71(9), b = 793.90(4), c = 727,35(5) pm, dx-ray = 4.99 g · cm?3, dpyc = 5.01 g · cm?3, Z = 2. Cs2Li14[Pb3O14]: a = 1295.28(12), b = 796.69(8), c = 732.44(7) pm, dx-ray = 5.31 g · cm?3, dpyc = 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. 相似文献