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1.
K3BiSe3, Rb3BiSe3, and Cs3BiSe3 – Derivatives of the Th3P4 Structure Type The compounds K3BiSe3, Rb3BiSe3, and Cs3BiSe3 were synthesized by heating mixtures of Bi2O3 and the respective alkalicarbonate in a stream of hydrogen saturated by selenium at 850°C. Thin crystals of the compounds appear red in transmitted light. They crystallize isostructural with Na3AsS3, space group P213, lattice constants a = 9.771(5) Å, a = 10.161(3) Å, and a = 10.587(5) Å for K3BiSe3, Rb3BiSe3, and Cs3BiSe3, respectively. The Na3AsS3 structure type is a derivative of the Th3P4 structure type.  相似文献   

2.
The Crystal Structure of Cu3SbSe3 The hitherto unknown crystal structure of Cu3SbSe3 has been determined from single crystals. The compound crystallizes in the orthorhombic system, space group Pnma (No. 62), with a = 7.9865(8), b = 10.6138(9) and c = 6.8372(7) Å, V = 579.6(1) Å3, Z = 4. Most remarkable feature of the structure are groups of three cis-edge-sharing tetrahedra [Cu3Se8] which are interlinked to a threedimensional arrangement by SbSe3-units. In contrast to Cu3SbS3 in the temperature range from ?180 to 25°C no hints for a phase transition could be detected by means of X-ray- and thermoanalytical methods.  相似文献   

3.
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   

4.
Three Novel Selenoborato- closo -dodecaborates: Syntheses and Crystal Structures of Rb8[B12(BSe3)6], Rb4Hg2[B12(BSe3)6], and Cs4Hg2[B12(BSe3)6] The three selenoborates Rb8[B12(BSe3)6] (P1, a = 10.512(5) Å, b = 10.450(3) Å, c = 10.946(4) Å, α = 104.53(3)°, β = 91.16(3)°, γ = 109.11(3)°, Z = 1), Cs4Hg2[B12(BSe3)6] (P1, a = 9.860(2) Å, b = 10.740(2) Å, c = 11.078(2) Å, α = 99.94(3)°, β = 90.81(3)°, γ = 115.97(3)°, Z = 1), and Rb4Hg2[B12(BSe3)6] (P1, a = 9.593(2) Å, b = 10.458(2) Å, c = 11.131(2) Å, α = 99.25(3)°, β = 91.16(3)°, γ = 116.30(3)°, Z = 1) were prepared from the metal selenides, amorphous boron and selenium by solid state reactions at 700 °C. These new chalcogenoborates contain B12 icosahedra completely saturated with six trigonal-planar BSe3 entities functioning as bidentate ligands to form a persubstituted closo-dodecaborate anion. The two isotypic compounds Rb4Hg2[B12(BSe3)6] and Cs4Hg2[B12(BSe3)6] are the first selenoborate structures containing a transition metal which are characterized by single crystal diffraction.  相似文献   

5.
High-pressure Synthesis and Structure of Rb2PtH6 and Cs2PtH6, Ternary Hydrides with K2PtCl6-Structure The ternary platinum hydrides Rb2PtH6 and Cs2PtH6 were synthesized by the reaction of rubidium hydride and cesium hydride, respectively, with platinum sponge under a hydrogen pressure above 1 500 bar at 500°C. X-ray investigations on powdered samples and elastic neutron diffraction experiments on the deuterated compounds at the time-of-flight spectrometer POLARIS led to their complete structure determination. Their atomic arrangements are isotypic with that of K2PtCl6 containing isolated [PtH6]2?-octahedra (space group: Fm3 m, Z = 4).  相似文献   

6.
Carbonate Hydrates of the Heavy Alkali Metals: Preparation and Structure of Rb2CO3 · 1.5 H2O und Cs2CO3 · 3 H2O Rb2CO3 · 1.5 H2O and Cs2CO3 · 3 H2O were prepared from aqueous solution and by means of the reaction of dialkylcarbonates with RbOH and CsOH resp. in hydrous alcoholes. Based on four‐circle diffractometer data, the crystal structures were determined (Rb2CO3 · 1.5 H2O: C2/c (no. 15), Z = 8, a = 1237.7(2) pm, b = 1385.94(7) pm, c = 747.7(4) pm, β = 120.133(8)°, VEZ = 1109.3(6) · 106 pm3; Cs2CO3 · 3 H2O: P2/c (no. 13), Z = 2, a = 654.5(2) pm, b = 679.06(6) pm, c = 886.4(2) pm, β = 90.708(14)°, VEZ = 393.9(2) · 106 pm3). Rb2CO3 · 1.5 H2O is isostructural with K2CO3 · 1.5 H2O. In case of Cs2CO3 · 3 H2O no comparable structure is known. Both structures show [(CO32–)(H2O)]‐chains, being connected via additional H2O forming columns (Rb2CO3 · 1.5 H2O) and layers (Cs2CO3 · 3 H2O), respectively.  相似文献   

7.
The new quaternary compounds Cs2AgVS4, K2AgVSe4, Rb2AgVSe4, Rb2AgNbS4, and Cs2AgNbSe4 were prepared using the reactive flux method. In this structure type infinite chains of edge-sharing AgQ4- and MVQ4-tetrahedra are running parallel to the crystallographic a-axis. The chains are separated by alkali cations. A linear relationship between the size of the alkali cation A+ and the Q–Q interchain distances was found. These compounds are isostructural with the analogous quaternary copper chalcogenides. The optical properties were studied by collecting UV/Vis transmission and reflectance spectra which allowed to derive the optical band gaps. The colours of the vanadium compounds range from black to dark violet with optical band gaps between 1.7 and 1.8 eV. In addition, the behaviour of the samples was studied using polarized light. Under these experimental conditions the niobium compound Rb2AgNbS4 changes its colour from green to red when the direction of the polarization plane is changed by 90°.  相似文献   

8.
Ternary Halides of the A3MX6 Type I. A3YCI6 (A = K, NH4, Rb, Cs): Synthesis, Structures, Thermal Behaviour. Some Analogous Chlorides of the Lanthanides Reaction of the trichlorides MCl3 (M = Y, Tb? Lu) with alkali chlorides AC1 (A = K, Rb, Cs) in evacuated silica ampoules at 850?900°C yields A3MCl6-type chlorides. (NH4)3YCl6 is obtained via the ammonium-chloride route. The crystal structure of Rb3YCl6 (monoclinic, C2/c (no. 15), Z = 8, a = 2583(1)pm, b = 788.9(4)pm, c = 1283.9(7)pm, p = 99.63(4)°, R = 0.062, Rw = 0.050) is that of Cs3BiCl6. The Rb3YCl6/Cs3BiCl6 structure and the closely related structures of K3MoCl6 and In2CI3 are derived from the elpasolite-type of structure (K2NaAlF6) making use of the model of closest-packed layer structures. Cell parameters for the chlorides Rb3MCl6 (M = Y, Tb? Lu) and Cs3YCl6 and Cs3ErCl6 as well, which are all isostructural with Rb3YCl6, are given. The “system” (K, NH4, Rb, Cs)YCl6 has been investigated by DTA and high-temperature X-ray powder diffractometry.  相似文献   

9.
Preparation and Crystal Structure of the Dialkali Metal Trichalcogenides Rb2S3, Rb2Se3, Cs2S3, and Cs2Se3 Crystalline products were obtained by the reaction of the pure alkali metals with the chalcogens in the molar ratio 2:3 in liquid ammonia at pressures up to 3000 bar and temperatures around 600 K. The substances crystallize in the K2S3 type structure (space group Cmc21(NO. 36)). Unit cell constants see ?Inhaltsübersicht”?. The characteristic feature of this structure are bent polyanions X32?:(X = S,Se). The new described compounds are compared with the other known alkali metal trichalcogenides.  相似文献   

10.
Rb3CoO2 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursors (Co3O4, RbN3 and RbNO3) were heated in a special regime up to 500 °C and annealed at this temperature for 100 h in silver crucibles. The crystal structure of the obtained red product was solved and refined by powder methods (Pnma, Z = 4, 12.3489(2), 7.6648(1), 6.2251(1) Å). Rb3CoO2 is isostructural with K3CoO2 and contains Co1+, which is coordinated by two oxygen atoms forming a slightly distorted dumb‐bell. Rb3CoO2 decomposes at 580 °C to Rb2O, Co and CoO.  相似文献   

11.
New selenidoantimonats [Ni(dien)2]2Sb2Se6 ( 1 ), [Mn(dien)2]2(SbSe4)(Cl) ( 2 ), [Co(dien)2]2(SbSe4)(Br) ( 3 ), and [Co(dien)2]3(SbSe4)2 ( 4 ) (dien = diethylenetriamine) were solvothermally synthesized in dien solvent at 180 °C. The crystal structure of 1 consists of two octahedral [Ni(dien)2]2+ cations and a mixed‐valent [Sb2Se6]4? anion. The isolated [Sb2Se6]4? anion is formed by a SbIIISe3 trigonal pyramid and a SbVSe4 tetrahedron sharing a common corner. 2 and 3 are composed of octahedral [M(dien)2]2+ cations, tetrahedral [SbSe4]3? anions and halide ions forming an extended network through hydrogen‐bonding interactions. In 4 the [Co(1)(dien)2]2+, [Co(2)(dien)2]2+ and [SbSe4]3? ions form layered structures via N–H···Se hydrogen bonds. The [Co(3)(dien)2]2+ ion is located between the layers, and interacts with the layers by N–H···Se bonds. The synthesis and solid state structural studies on the title compounds show that the higher reaction temperature is helpful for the formation of selenidoantimonate(V) compounds in the synthesis of selenidoantimonate from the M2+/Sb/Se/dien system. 1 – 4 start to decompose at temperature about 210 °C in N2 atmosphere. They lose dien ligands at a wide temperature range of 210–450 °C with multisteps for 1 – 3 and a single step for 4 .  相似文献   

12.
Rubidium Hexaamidolanthanate and -neodymate, Rb3[La(NH2)6] and Rb3[Nd(NH2)6]; Compounds. Structurally Related to K3[Cr(OH)6] and K4CdCl6 Colourless Rb3[La(NH2)6] (a = 12.298(4) Å, c = 13.759(2) Å, N = 6, R3 c) and pale blue Rb3[Nd(NH2)6] (a = 12.199(6) Å, c = 13.626(4) Å, N = 6, R32) have been prepared by the reaction of the corresponding metals (Rb: La resp. Nd = 3:1) with NH3(P(NH3) = 4–4.5 kbar) at 300°C. Single crystal x-ray methods gave their structures. It is shown by space group relations that these compounds are structurally related to one another and to further ternary amides as well as to K3[Cr(OH)6] and K4CdCl6.  相似文献   

13.
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   

14.
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   

15.
Na3AsSe3 and K3AsSe3 – Synthesis and Crystal Structure The compounds Na3AsSe3 and K3AsSe3 were synthesized by heating mixtures of As2O3 and the respective alkalicarbonate in a stream of hydrogen saturated by selenium at 750 °C. The structures were determined from X-ray single-crystal diffractometer data. Both compounds crystallize isostructural with Na3AsS3, space group P213, Z = 4, lattice constants a = 8,925 (1) Å for Na3AsSe3 and a = 9,710(1) Å for K3AsSe3.  相似文献   

16.
The new ternary compounds Rb4Ti3S14, Cs4Zr3S14, K4Hf3Se14, and K4ZrHf2Se14 were prepared by reacting the respective transition metals in alkali metal polychalcogenide melts. Two crystallographically independent transition metal cations are present that are coordinated by eight chalcogen atoms (Q) in an irregular fashion or by seven chalcogen atoms yielding a distorted pentagonal bipyramid. The M(1)Q8 and M(2)Q7 polyhedra are connected by sharing common edges or trigonal faces leading to the formation of infinite linear one‐dimensional anionic chains running parallel to the [101] direction. The chains are separated by alkali metal cations. The optical band gaps determined are 1.59 eV for Rb4Ti3S14, 2.35 eV for Cs4Zr3S14, and 2.02 eV for K4Hf3Se14. In‐situ X‐ray powder diffractometry demonstrates that Rb4Ti3S14 decomposes at 430 °C into Rb2S5 and TiS. During the cooling cycle the re‐formation of the polysulfide is observed. According to this result the polysulfide could be prepared using TiS instead of metallic Ti as well.  相似文献   

17.
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   

18.
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   

19.
On Hexafluorocuprates (III) New prepared are: Cs2LiCuF6 (green, trigonal isotypic to Cs2LiGaF6; a = 621.5, c = 503.3 pm, γ = 120° from CsCuCl3, CsCl, Li2CO3, pF2 = 1 bar, 350°C, 2w); K2LiCuF6 (green, cubic isotypic to K2NaCrF6; a = 792.5 pm from KCuCl3, Li2CO3, KCl, pF2, = 35 bar, 480°C, 3 d); CsRb2CuF6 (green, cubic isotypic to inv. K2NaCrF6; a =899,6 pm from CsCuCl3, RbCl, pF2 = 1 bar, 400°C, 7 d); CsRbKCuF6 (green, cubic isotypic to K2NaCuF6; a = 886.1 pm from KCuCl3, CsCl, RbCl, pF2 = 1 bar, 400°C, 7 d); CsCuCuF6 (black, orthorhombic isotypic to CsNiNiF6; a = 706.7, b = 727.7, c = 1032.2 pm from CsCuCl3, CuCl2 · 2H2O, pF2 = 30 bar, 400°C, 20 h); CsBaCuF6 (green, tetragonal; a = 598.1, c = 864.6 pm from ?BaCuO2’?, CsCl, pF2 = 350 bar, 400°C, 7 d). Also prepared: Cs2RbCuF6, Cs2KCuF6, Cs2NaCuF6, Rb2KCuF6, Rb2NaCuF6, Rb2LiCuF6, K2NaCuF6, Na3CuF6, K3CuF6, Rb3CuF6, Cs3CuF6 and CsZnCuF6 (parameters see text). The Madelungpart of Lattice Energy, MAPLE are calculated and discussed. All samples are paramagnetic and follow (exception: CsZnCuF6) the Curie-Weiss-Law.  相似文献   

20.
Reactivity in the Systems A/Cu/M/O (A = Na–Cs and M = Co, Ni, Cu, Ag); Synthesis and Crystal Structures of K3Cu5O4 und Cs3Cu5O4 The systems A/Cu/M/O with A = Na–Cs and M = Co, Ni, Cu, Ag have been investigated with preparative, thermoanalytical and in situ X‐ray techniques to study the reactivity. For the redox reaction Co/CuO in the presence of Na2O the intermediate, NaCuO, has been characterized. K3Cu5O4 was obtained by annealing intimate mixtures of K2O and CuO (molar ratio 1 : 1) in Ag containers at 500 °C. Cs3Cu5O4 could be synthezised by reaction of KCuO2 with Cs2O (molar ratio 1 : 1) in Cu containers at 500 °C. Both compounds crystallize in the space group P21/c with Z = 4 isotypic to Rb3Cu5O4 [IPDS data, Mo–Kα; K3Cu5O4: a = 946.0(1), b = 735.61(6), c = 1401.3(2) pm, β = 107.21(1)°; 2249 F2(hkl), R1 = 7.09%, wR2 = 11.42%; Cs3Cu5O4: a = 1027.7(1), b = 761.42(7), c = 1473.4(2) pm, β = 106.46(1)°, 1712 F2(hkl), R1 = 6.04%, wR2 = 14.22%]. Force constants obtained from FIR experiments for the deformation mode δ(O–Cu–O), the Madelung Part of the Lattice Energie, MAPLE, Effective Coordination Numbers, ECoN, calculated via Mean Effective Ionenradii, MEFIR, are given.  相似文献   

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