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1.
On Perovskite Phases of the System Ba2Y0,67U1?xWxO6 A solid solution series is formed between the polymorphic perovskites Ba2Y0.67UO6 and Ba2Y0.67WO6 (cubic: a = 8.372 Å; hexagonal: a = 4× 5.881 Å and c = 4× 7.778 Å). The structure is cubic between x = 0.1 and 0.99 and for x > 0.95 hexagonal as well. Strong deviations from the ideal behaviour are detectabel with spectroscopic methods. The shape of the UO6 and WO6 octahedrons experiences only minor changes within the series.  相似文献   

2.
New obtained is K2Cd2O3 (brownish red), which – according to single crystal work [487 h 01–h 41, Mo? Kα, R = 9.73%, R′ = 10.76%] – crystallises monoclinic with a = 6.417, b = 6.723, c = 6.586 Å, β = 116.0° in P21/c–C [K+, Cd2+ and O(1)2? in 4(e), O(2)2? in 2(a)] and is isotypic with Na2Zn2O3. [Parameters see text]. The Madelung Part of Lattice Energy is calculated and discussed.  相似文献   

3.
On Na2PrO3 and Na2TbO3 Using an exchange reaction of Na2O with Li8TbO6 (Na : Tb = 2.1 : 1; au-tube; 750°C, 30 d) yellow-orange colored single crystals of Na2TbO3 could be prepared for the first time. Na2TbO3 crystallizes monoclinic in C2/c (Z = 8; a = 576.92(6), b = 1001.27(9), c = 1117.91(14) pm, β = 99.98(1)°). According to four-circle data the Li2SnO3-type of structure is adopted (PW 1100, MoKα , 1935 I0 (hkl), R = 4.86%, Rw = 3.63% for all 928 unique reflexions). By a similar exchange reaction of Na2O with Li8PrO6 for the first time single crystals of Na2PrO3 could be prepared, too (Na : Pr = 2.2 : 1; au-tube; 700°C; 23 d). The structure determination reveils that there is a variant of the NaCl-type of structure, which ressembles to the Li2SnO3-type of structure (PW 1100, MoKα , 2199 I0 (hkl)), R = 8.88%, Rw = 5.21% for all 947 unique reflexions; C2/c, Z = 8, a = 678.78(5), b = 977.47(7), c = 1080.38(9) pm, β = 108,4(1)°. In contrast to Na2TbO3 there are no layers according to NaO(Na1/3Tb2/3)O. All octahedral intersticies are occupied systematically with Pr4+ and Na+ : (Na2/3Pr1/3)O(Na2/3Pr1/3)O.  相似文献   

4.
On Oxothorates of the Alkaline Metals: K3NaTh2O6 For a first time single crystals of a (in addition: new) oxothorate were prepared starting with the binary oxides [1 200°C, 4d, then 1 300°C, 5d, Ni-bomb; powder: 650°C, 10d, Ag-bomb]. The colourless, transparent single crystals are monoclinic, C2/c, a = 629.64 pm, b = 1 089.93 pm, c = 1 259.75 pm, β = 99.66°, z = 4, Dx = 5.458 g cm?3 and Dpyc = 5.456 gcm?3. It is an ordered variant of the NaCl-type; MoKα, fourcircle diffractometer data (PW 1100), R = 7.67 and Rw = 7.35% for 1 083 of 1 236 I0 (hkl). The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.  相似文献   

5.
On a New Modification of Na2C2 On heating NaC2H to temperatures between 80 °C and 150 °C in vacuum two coexisting modifications of Na2C2 are observed, as was shown by temperature dependent X‐ray powder diffraction. The known modification I (I41/acd, Z = 8) and a previously unknown modification II could be identified, which is isotypic to Li2C2 (Rb2O2 structure type, Immm, Z = 2). Modification II is also stable on cooling to room temperature, but a complete conversion of NaC2H to Na2C2‐II could not be achieved up to now. Heating to temperatures above 150 °C leads to a complete conversion of Na2C2‐II to Na2C2‐I. According to MAPLE calculations Na2C2‐I represents the thermodynamically stable modification at room temperature.  相似文献   

6.
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-C32h; 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.  相似文献   

7.
The System Cs/Cu/F: On CsCuIICuIIIF6 ?CsCuF3,6’? is described in literature as a darkbrown powder which is supposed to crystallize in a cubic lattice (a = 882 pm, Debyeogramms). However Guinier photographs show that ?CsCuF3,6’? is a mixture of CsCuIICuIIIF6 (black, isotypic to CsNiIINiIIIF6, a = 706.7 b = 727.7, c = 1032.2 pm, Z = 4) and Cs2CuCuIIIF6 (auburn, pseudocubic, a = 623.4 c = 886.4 pm, Z = 2).  相似文献   

8.
Polythermal Curves of the Quinary System Na+, K+, Mg2+/Cl?, SO//H2O in Range between +25°C and ?10°C Proceeding from the 0°C, ?5°C and ?10°C isothermal curves of the quinary system Na+, K+, Mg2+/C1?, SO//H2O with saturation at NaCl, KCl, and carnallite, respectively, the polythermal curve is represented between 25°C and ?10°C. Within the new defined range of the polythermal curve the invariant five-salt-paragenesis NaCI, KCI, Glauber's salt (Na2SO4 · 10 H2O), bitter salt (MgSO4 · 7 H2O), Schoenite (K2SO4 · MgSO4 · 6 H2O) can be found at ?7,2°C. It represents also the lowest temperature of formation of Schoenite in this system. It was necessary, moreover, to reconsider further univariant and invariant equilibrium solutions in the range between 25° and 0°C.  相似文献   

9.
10.
On the Crystal Structures of CH3PF2H+AsF6? and CH3PF2H+SbF6? and a simple Method for Preparation of CH3PF2 A simple method for preparation of CH3PF2 from CH3PCl2 is reported. The phosphonium salts CH3PF2H+MF6? are obtained by the reaction of CH3PCl2 with superacidic systems HF/MF5 (M = As, Sb). CH3PF2H+SbF6? crystallizes in the space group P1 with a = 548.4(4) pm, b = 695.5(8) pm, c = 960.2(9) pm, α = 94.68(5)°, β = 97.19(6)°, γ = 94.41(6)° and Z = 2. CH3PF2H+SbF6? crystallizes in P1 with a = 554.3(3), b = 724.2(4), c = 970.4(5), α = 94.73(4)°, β = 96.14(5)°, γ = 95.30(4)°.  相似文献   

11.
On the Quasi-Binary Systems NaNO2/Na2O and NaCN/Na2O. Phase Diagrams and Sodium Ion Conductivity of Na3O(NO2) and Na3O(CN) Measurements of the electrical conductivities of Na3O(NO2) and Na3O(CN) show sharp increases in conductivity at temperatures between 200° and 250°C, According to the phase diagrams of the quasi-binary systems NaNO2/Na2O and NaCN/Na2O this is not an effect established by fusion. It seems to be a consequence of a “melting” of the sodium sublattice or the rotational disorder of complex anions.  相似文献   

12.
Compounds of Type Ba2BIIIOsVO6 The black perovskites of type Ba2BIIIOsVO6 crystallize cubic (BIII ? Pr, Nd, Sm—Lu, Y) and rhombohedral (BIII ? La) respectively; the cell volumina decrease linearily with (rBIII)3. Intensity calculations on powder data for Ba2YOsO6 (space group Fm3m—O) and Ba2LaOsO6 (space group R3m—D) gave the intensity related R′ values of 4.6% and 5.0% respectively. The results of the vibrational spectroscopic investigations are reported in common with the bond orders, M? O distances and mean amplitudes and compared with the corresponding values of the series Ba2BIIIIrVO6 and Ba2BIIIRuVO6.  相似文献   

13.
Alkali-hexachlorochromates(III): Na3CrCl6 X-ray investigations on single crystals yielded for Na3CrCl6 a trigonal structure: space group P3 1c; a = 682.0(3) pm; c = 1203.4(5) pm; Z = 2. In a hexagonal-close arrangement of Cl? ions, 2/3 of the octahedral holes are occupied orderly by Na+ and Cr3+ ions. The Na compounds of V3+ and Mo3+ are isotypic. The chlorochromates with K and Rb are crystallizing with the K3MoCl6 structure according to X-ray photos of powders. The alkali metal ions habe the C.N. 8 or 11 related to the chloride ions. These compounds and elpasolithes A2BCrCl6 (A = Cs? K; B = Rb? Na) can be treated in the same way with the concept of tolerance factors as it is known for the chloro-perovskites AMCl3. For all compounds the temperatures of phase transitions were determined by DTA. Some structures could be solved from high-temperature-Guinier-patterns, by comparing them with patterns of substances with known structures.  相似文献   

14.
On a Possibility of Calculation of the Chemical Transport Behaviour of Ternary and More Complicated Solids Relations are deduced in order to describe the transport behaviour of phases with a homogeniety range or of several solid phases in equilibrium in ternary and more complicated systems. In analogy to binary systems the transport behaviour can be predicted on the base of a thermodynamic analysis of the heterogeneous equilibria.  相似文献   

15.
On the Alkali Selenoarsenates(III) KAsSe3 · H2O, RbAsSe3 · 1/2 H2O, and CsAsSe3 · 1/2 H2O The alkali selenoarsenates(III) KAsSe3 · H2O, RbAsSe3 · 1/2 H2O, and CsAsSe3 · 1/2 H2O have been prepared by hydrothermal reaction of the respective alkali carbonate with As2Se3 at a temperature of 135°C. Their X-ray structural analyses demonstrated that the compounds contain polyselenoarsenate(III) anions (AsSe3?)n, in wich the basic units are ψ-AsSe3 tetrahedra, which are linked together through Se? Se bonds into infinite zweier single chains. The Rb and Cs salts are isotypic.  相似文献   

16.
Glass Formation and Properties of Chalcogenide Systems. XIII. On the Compounds Na6Ge2S6 · 4 CH3OH and Na6Ge2Se6 · 4 CH3OH The glasses Ge2S3 and Ge2Se3 are soluble in solutions of Na2S or Na2Se in CH3OH forming Na6Ge2S6 · 4 CH3OH and Na6Ge2Se6 · 4 CH3OH. On heating the CH3OH-free substances are formed. From the i.r. and Raman spectra can de seen that the structure of the ions Ge2S, Ge2Se, P2S64?, and of Si2Cl6 is of the same type. The formation of the compounds can be regarded as a chemical proof for the existence of [Ge2S6] and [Ge2Se6] units as structural groups in the glasses Ge2S3 and Ge2Se3.  相似文献   

17.
Oxoargentates(I) of Alkali Metals. On Na3AgO2 Na3AgO2 has been prepared anew (light pale-yellow powder samples; clear transparent single crystals). It crystallizes orthorhombic (space group Ibam) with a = 5.463, b = 10.926, c = 5.926 Å, Z = 4, d = 3.94 g X cm?3, dpyk = 3.89 g X cm?3; parameters are given in the text. The structure of Na3AgO2, marked by linear “dumb-bells” [O? Ag? O], d(Ag→O) = 2.09 Å is a novel variant of Na2O. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, have been calculated and are discussed.  相似文献   

18.
19.
On Hexafluorovanadates(III). Cs2MVF6 and Rb2MVF6 (M?Tl, K. and Na); with a Remark on Na3VF6 By heating the binary fluorides in a closed system we obtained Cs2TlVF6 (a = 9.234 Å), Cs2KVF6 (a = 9.047 Å), Rb2KVF6 (a = 8.855 Å) and Rb2NaVF6 (a = 8.468 Å), all cubic Elpasolithes of soft green colour as well as Cs2NaVF6 (hexagonal a = 6.24 Å, c = 30.58 Å, isotypic with Cs2NaCrF6) and Na3VF6 (monoclinic a = 5.513 Å, b = 5.721 Å, c = 7.963 Å, β = 90.47°, isotypic with Na3AlF6). VF3 (3.0–296.2°K), Cs2TlVF6, Cs2KVF6 and Rb2KVF6 (all from 70–299°K) have been measured magnetically. The spectra of reflection in the range of 9 000 to 33 000 cm?1 of VF3 and the new quaternary fluorides are measured and discussed. The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.  相似文献   

20.
Newly prepared are the cubic derivatives of the perovskite type of structure: K2NaInF6 (a = 8.560 Å), K2NaTlF6 (8.668), K2NaScF6 (8.482), K2NaYF6 (8.711), Cs2NaInF6 (8.905), Cs2NaTiF6 (8.995), Cs2NaScF6 (8.853), all colourless, as well as K2NaCuF6 (8.203 Å, green) and Cs2KMnF6 (tetragonal, a = 8.933; c = 9.265 Å, violett). K2NaCuF6 [μ = 2.87 μB, θ = ?17°] and Cs2KMnF6 [;μ = 4.88 μB, θ = ?5°] obey the Curie-Weiss law. The volume chemistry of the compounds is discussed in detail.  相似文献   

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