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1.
About Alkali Seleno Bismuthates (III), with a Comment Regarding the Th3P4 Structure Type The synthesis and X-ray single crystal structure determination of the ternary selenides Rb3BiSe3, Cs3BiSe3, and RbK2BiSe3 are described. The compounds were synthesized via a reaction of Bi2O3 with the alkali carbonate in a selencharged hydrogen stream at 850°C. They crystallize in the Na3AsS3 structure type (space group P213). In the discussion of the structure, the aristotypic Th3P4 structure is included.  相似文献   

2.
Crystal Structure of Cs2PrO3 and also about Cs2CeO3, Cs2TbO3, Rb2CeO3, and Rb2TbO3 New prepared Cs2PrO3 (dark brown) is orthorhombic due to single crystal data, K2PbO3 type of structure (Cmc21) with a = 11.47, b = 7.722, c = 6.427 Å and Z = (4). Cs2CeO3 (colourless, a = 11.495, b = 7.753, c = 6.437 Å), Cs2TbO3 (red-brown, a = 11.37, b = 7.726, c = 6.142 Å), and the low-temperature form of (LT-) Rb2TbO3 (red-brown, a = 10.91, b = 7.390, c = 6.099 Å) are isotypic. Hitherto unknown HT-Rb2CeO3 (high-temperature form, colourless, a = 3.837, c = 18.47 Å, Z = 2, hexagonal) and “HT-Rb2TbO3” (red-brown, a = 3.773, c = 18.00 Å) correspond according to powder-data to the α-NaFeO2 type of structure. Cs2PrO3 has been measured magnetically (100–300 K). The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.  相似文献   

3.
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   

4.
The two title trialkaline trioxoantimonates(III), tripotassium trioxoantimonate(III), K3[SbO3], (I), and tricaesium trioxo­antimonate(III), Cs3[SbO3], (II), crystallize in the cubic Na3[AsS3] structure type in space group P213. The structures show discrete Ψ-tetrahedral [SbO3]3− anions with C3v point-group symmetry. The Sb—O distances are 1.923 (4) Å in (I) and 1.928 (2) Å in (II), and the O—Sb—O bond angles are 99.5 (2)° in (I) and 100.4 (1)° in (II).  相似文献   

5.
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   

6.
New Oxocuprates(I). On Cs3Cu5O4, Rb2KCu5O4, RbK2Cu5O4 and K3Cu5O4 Cs3Cu5O4 light yellow, powder as well as single crystals [a = 10.313(9), b = 7.630(1), c = 14.750(4) Å, β = 106.48(6)°], Rb2KCu5O4 [a = 9.724(2), b = 7.443(0), c = 14.246(2) Å, β = 106.78(8)°], RbK2Cu5O4 [a = 9.561(1), b = 7.411(0), c = 14.111(1) Å, β = 106.76(7)°] and K3Cu5O4 [a = 9.422(1), b = 7.364(1), c = 13.995(2) Å, β = 107.00(2)°] are new prepared. The colour of the powders becomes lighter according to the sequence showed above. K3Cu5O4 shows pale yellow. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.  相似文献   

7.
The crystal chemistry of the valence stable Thorium (Th4+) shows in oxovanadates, ‐niobates, ‐molybdates, ‐tantalates etc. typical cationic property. It depends on the big size of the Th4+ ion in the order of r(Th4+) = 0.92 Å (C.N. = 6) up to r(Th4+) = 1.34 Å (C.N. = 12), comparable with the radii of alkaline and alkaline earth metals: r(Na+) = 1.02 Å (C.N. = 6) or r(K+) = 1.5 Å (C.N. = 8); r(Ca2+/Sr2+) = 1.1 Å/1.26 Å (C.N. = 8). There exists only one typical compound that may be of the oxothorate type with the composition NaK3Th2O6. Na+ and K+ can be declared to be components of the cationic part of the crystal structure. In contrary, thorium and oxygen are common components of the anionic part of the crystal structure. From the point of view of the shared polyhedra (exclusively octahedra), NaK3Th2O6 belongs to the thorium‐oxometallates too. The report on oxometallates of thorium shows compounds with one, two, four and five Th4+ atoms in combination with V5+, Nb5+, Ta5+ and Mo6+. W6+ is completely missing. Some of the Tantalates belong to the Jahnberg compounds, showing planar nets of corner shared pentagonal bipyramids. ThMO4 and cationic mixed compounds, Th1–xAxMO4, crystallize with the Scheelite (respectively Huttonite) structure and at least Th4+ is part of ordered and disordered perowskites showing more or less deviations from the cubic symmetry.  相似文献   

8.
On Oxoberyllates of the Alkali-Metals The existence of the phases K2Be2O3 (2 forms), K4BeO3, Rb2Be3O4, Rb2Be2O3,Rb4BeO3, Cs2Be3O4 and Cs2BeO2 is proved by powder-datas according to GUINIER -SIMON . In single crystal form we obtained Li4BeO3 [a = 5.49; b = 9.53; c = 4.93 Å; a = 114.1; ß = 105.0; γ = 106.6°; triclinic], Na2Be2O3 [;a = 6.32; b = 8.53; c = 2.71 Å; α = 107.7; ß = 105.5; γ = 78.4°; triclinic], Na6Be2O5 [a = 5.672; c = 10.21 Å; tetragonal] as also K2BeO2 [a = 7.098; b = 10.577; c = 5.706 Å; γ = 131.3°; monoclinic] and Rb2BeO2 [a = 7.463; b = 11.170; c = 5.881 Å; γ = 131.8°; monoclinic].  相似文献   

9.
New fluoroperovskites with CrIII and MnIII: A(B0.5Cr0.5)F3 and A(B0.5Mn0.5)F3; A, B = alkali We obtained Cs2KCrF6 (a = 9.004 Å), Rb2KCrF6 (a = 8.817 Å), Rb2NaCrFe(a = 8.418 Å) (all green, K2NaCrF6-type) and Cs2NaCrF8 as well as Rb2NaMnF6 (tetragonally distorted K2NaCrF6-type; a = 8.365, c = 8.660 Å; F4/mmm), and Rb2KMnF6 and Cs2NaMnF6, all violet. Jahn-Teller-distortion and lattice energy of Rb2NaMnF6 and K2NaMnF6 are discussed.  相似文献   

10.
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   

11.
Zintl‐Compounds with Gold and Germanium: M3AuGe4 with M = K, Rb, Cs Black, brittle single crystals of M3AuGe4 with M = K, Rb, Cs were synthesized by reactions of alkali metal azides (MN3) with gold sponge and germanium powder at T = 1120 K. The structures of the compounds (space group Pmmn, Z = 2, K3AuGe4: a = 6.655(1)Å, b = 11.911(2)Å, c = 6.081(1)Å; Rb3AuGe4: a = 6.894(1)Å, b = 12.421(1)Å, c = 6.107(1)Å; Cs3AuGe4: a = 7.179(1)Å, b = 12.993(2)Å, c = 6.112(2)Å) were determined from X‐ray single‐crystal diffractometry data. The semiconducting compounds contain equation/tex2gif-stack-2.gif[AuGe4]‐chains with P4‐analogous Ge4‐tetrahedra which are connected by μ2‐bridging gold atoms in a distorted tetrahedral Ge‐coordination.  相似文献   

12.
On Oxoniccolates(II) of Alkali Metals: K2NiO2, Rb2NiO2, and Cs2SiO2. The hitherto unknown K2NiO2 (dichroic single crystals: redviolet/green, a=3.953, c=12.853 Å), Rb2NiO2 (analogous yellowred/green, a=4.174, c=13.186 Å) and Cs2NiO2 (analogous: darkgreen/green, a=4.413, c=13.590 Å) have been obtained, which surprisingly crystallize in the tetragonal Na2HgO2-type of structure with [O–-Xi –-O]-dump-bells. The distance Ni –-O is very short: 1.68 Å. The K2SiO2-structure was determined using single crystal data, R=7.98% and R′=10.6% for 131 reflections hhl–- (h+3)hl. The magnetic datas for K2NiO2 and Cs2NiO2 obey the CURIE -WEISS -law (μ=3,0 μB. Θ ? ?30°K). The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.  相似文献   

13.
On Ordered Variants of the NaCl Type of Structure: New Cubic Forms of NaMO2 (M = Sc, Y, Dy, Tm, Yb, Lu), K2MO3, Rb2MO3 (M = Ce, Pr, Th), and Cs2ThO3 We obtained hithertoo unknown cubic forms of NaScO2 (a = 4.525 Å), NaYO2 (a = 4.791 Å), NaDyO2 (a = 4.800 Å), NaTmO2 (a = 4.743Å), NaYbO2 (a = 4.730 Å), NaLuO2 (a = 4.715 Å) [all colourless], K2CeO3 (a = 5.203 Å), K2PrO3 (a = 5.185 Å), K2ThO3 (a = 5.308 Å), Rb2CeO3 (a = 5.397 Å), Rb2PrO3 (a = 5.367 Å), Rb2ThO3 (a = 5.475 Å), and Cs2ThO3 (a = 5.704 Å) [colour see ins.] by heating mixtures of the binary oxides AOx (A = Na, K, Rb, Cs) with active forms of M2O3, respectively. It is discussed MO2, how one may understand the existence of the cubic forms, which according to powder data show a statistical distribution of cations (with different charge and ionic radius).  相似文献   

14.
News on K2[MnF6], Rb2[MnF6], and Cs2[MnF6] Cs2[MnF6] (a = 8.972 Å) and Rb2[MnF6] (a = 8.531 Å) as well as this with K2[MnF6] (a = 8.221 Å and hexagonal a = 5.722, c = 9.331 Å) form mixed crystals of the K2PtCl6 type of structure. Calculations of the Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, lead contrary to former assumptions to distances Mn? F of about 1.86 Å (CN 6).  相似文献   

15.
New Elpasolithes with CoIII: 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.  相似文献   

16.
On Hexafluoroferrates(III): Cs2TlFeF6, Cs2KFeF6, Rb2KFeF6, Rb2NaFeF6, and Cs2NaFeF6 New prepared are the compounds Cs2TlFeF6 (a = 9.211 Å), Cs2KFeF6 (a = 9.041 Å), Rb2KFeF6 (a = 8.868 Å) and Rb2NaFeF6 (a = 8.46 4Å) all cubic Elpasolithes as well as Cs2NaFeF6 (Cs2NaCrF6?type, hexagonal with a = 6.281, c = 30.532 Å), all colourless. Cs2KFeF6 was measured magnetically (70–297,2 K). The spectra of reflection were measured (9000–36000 cm?1). The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.  相似文献   

17.
Novel Hexafluoromolybdates(III): Cs2MMoF6, Rb2MMoF6, TI2MMoF6 (M = K, Na), and Cs2TIMoF6. With a Notice on MoF3 MoF3, light yellow, hexag., a = b = 5.21, c = 14.41 Å, pure prepared by a new method, forms at higher temperatures with the corresponding Fluorides AF the hitherto unknown compounds Cs2KMoF6 (a = 9.20 Å), Cs2TlMoF6 (a = 9.392 Å). Rb2KMoF6 (a = 8.911 Å), Rb2NaMoF6 (a = 8.632 Å), Tl2KMoF6 (a = 8,977 Å), Tl2NaMoF6 (a = 8.649 Å) and K2NaMoF6 (a = 8.501 Å), all cubic Elpasolithes and all light yellow. The magnetic properties of MoF3 (100.4–295.2 K) and Tl2NaMoF6 (81.4–251.3 K) are investigated. The spectra of reflection were measured (15000–36000 cm?1). The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.  相似文献   

18.
19.
Oxidation Products of Intermetallic Compounds. III. Low Temperature Forms of K2Sn2O3 and Rb2Sn2O3 and a Notice about K2Ge2O3 By controlled oxidation of KSn (at 320°C) and RbSn (at 410°C) with O2 the hitherto unknown low temperature forms of K2Sn2O3 (a = 8.4100(8) Å) and Rb2Sn2O3 (a = 8.6368(8) Å) are obtained, which are isotopic with cubic K2Pb2O3. Oxidation at higher temperatures (at 510–5207°C) leads to the well-known HT-forms. The Madelung Part of Lattic Energie, MAPLE, is calculated for both compounds. K2Pb2O3, Rb2Pb2O3, Cs2Pb2O3, and Cs2Sn2O3 have been prepared too by oxidation of KPb, RbPb, CsPb, and CsSn. Oxidation of KGe (at 400°C) leads to the first oxogermanate(II), K2Ge2O3 (cubic a = 8.339(1) Å, isotypic with K2Pb2O3) together with K6Ge2O7.  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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