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The Crystal Structure of CsTcO4 CsTcO4 crystallizes orthorhombic with a = 5.727, b = 5.921 and c = 14.34 Å. Z = 4, space group Pnma (Nr. 62, I.T.). The metal positions were refined by single crystal data, the oxygen positions first determined: the CsTcO4 structure is a slight distortion of the scheelite arrangement (parameters: see text). The MADELUNG Part of Lattice Energy, MAPLE, ?Mean Effective Ionic Radii”?, MEIR, and Effective Coordination Numbers, ECoN, are calculated and discussed. 相似文献
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Li2SnO3 crystallises monoclinic, C, with a = 5.295, b = 9.184, c = 10.032 Å and β = 100.13°; Z = 8. The positions of Sn were obtained from PATTERSON maps and the positions of O and Li by FOURIER difference method. Parameters were refined by least squares-method [1462 reflexes (h 01)–(h 71); R = 10.5%]. The average distances of Li? O are 2.07 Å, and 2.20 Å for Sn? O. The Li2SnO3 structure can be derived from the NaCl type: in a cubic closest packing of oxygen 2/3 of the octahedral holes are occupied by lithium and 1/3 by tin. 相似文献
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Magnetochemistry of Divalent Silver. New Fluoroargentates(II): Cs2AgF4, Rb2AgF4, and K2AgF4 Hitherto unknown blue compounds Rb2AgF4 and Cs2AgF4 are prepared. Guinier patterns show, that Cs2AgF4 cristallise in the K2NiF4 structure (a = 4.581, c = 14.192 Å). The structure of the Rb-compound is still unknown. The magnetic behaviour of K2AgF4, Rb2AgF4, and Cs2AgF4 is discussed. 相似文献
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New Nesozincates: K4[ZnO3], Rb7Na[ZnO3]2 For the first time A) K4[ZnO3] and B) Rb7Na[ZnO3]2 have been prepared (from the binary oxides). They represent the first oxozincates of the alkali metals in which the coordination number of Zn2+ is exclusively 3 (carbonate-like groups [ZnO3]). Both oxides crystallize triclinic, space group P1 with A): a = 1103.3(3), b = 881.3(3), c = 698.2(2) pm, α = 109.65(2)°, β = 89.56(2)°, γ = 102.41(3)° and Z = 4, and B): a = 1128.3(3), b = 974.5(3), c = 711,8(2) pm, α = 114.12(2)β, = = 88.46(3)°,γ = 106.48(2)° and Z = 4. Their crystal structures have been determined from single crystal data (four circle diffractometer) and refined to R = 10.1%, Rw = 7.8% (2905 unique I0(hkl)) and R = 19.5%, Rw = 17.3% (2269 unique I0(hkl)), respectively. The Madelung Part of Lattice Energy (MAPLE), Effective Coordination Numbers (ECoN) and Mean Fictive Ionic Radii (MEFIR) have been calculated. 相似文献
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About Perrhenates. 1. On LiReO4 For the very first time anhydrous LiReO4 was prepared in transparent, colourless single crystals from Li2O2 and Re2O7 (closed Au-pipe; 350°C; 14 d). The crystal structure, P1 , with a = 9.652(1), b = 8.455(1), c = 6.928(1) Å, α = 101,53° (1), β = 106.55° (1), γ = 97.22° (1), Z = 6, dx = 4.92 g/cm3, dpyk = 4,81 g/cm3 was solved (four-circle-diffractometer data PW 1100, 2151 I0 (hkl), AgKα; R = 0.073, Rw = 0.076). There are three kinds of functionally different Li+. The Madelung Part of the Lattice Energy, MAPLE, was calculated. 相似文献
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Thermal Behaviour of Li3MnO4. II. α- and β-Li2MnO3 By thermal decomposition of Li3MnO4 we obtained two new forms of Li2MnO3: α-Li2MnO3 crystallizes due to Guinier-Simon photographs cubic face-centered with a = 4.092 Å, β-Li2MnO3 hexagonal with a = 4,93, c = 14.24 Å, c/a = 2.89. α-Li2MnO3 is paramagnetic with μ = 3,82 B.M. Below the Neel temperature (≈? 50 K) β-Li2MnO3 is antiferromagnetic. Effective Coordination Numbers, ECoN, are calculated and discussed. 相似文献
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New Oxoterbates(IV) with Lithium: On Rb2Li14[Tb3O14] and Li6Tb2O7 For the first time we prepared Rb2Li14[Tb3O14] as yellow single crystals from Li8TbO6 and Rb2O (Tb:Rb = 1:2) [Ag-cylinder, 500°C, 30 d, then Au-tube, 700°C, 27 d]. The structure refinement [652 I0 (h kl), four circle diffractometer Philips PW 1100, ω-scan, MoKα, R = 4.69%, Rw = 3.24%, absorption considered, Immm with a = 1 283.07(10), b = 790.87(7), c = 736.87(7)pm, Z = 2, dx = 4.30 g · cm?3] confirms that it is isotypic with K2Li14[Pb3O14]. Furthermore we got for the first time Li6Tb2O7 as a bright yellow compound from Li2O2 and “Tb4O7*” [(Li:Tb = 3.4:1), Au-ube, 750°C, 13 d (powder), 850°C 22 d (single crystals)] and by thermal decomposition of Rb2Li14[Tb3O14] (Au-tube, 850°C, 25 d). Powder and single crystal data [1 327 I0 (h kl), four circle diffractometer PW 1100, ω-scan, AgKα, R = 9.38%, Rw = 5.23%, absorption not considered, P21/a, a = 1 056.30(10), b = 613.50(4), c = 546.56(5) pm, β = 109.668(7)°, Z = 2, dx = 4.67 g · cm?3 dpyc = 4.53 g · cm?3] reveal a new type of structure that may be deduced by the NaCl-type of structure. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed. 相似文献