Rb3ReH10, ein neues Hydrid des siebenwertigen Rheniums – Hochdrucksynthese und Kristallstruktur

Rb₃ReH₁₀, a New Rhenium(VII) Hydride – High Pressure Synthesis and Crystal Structure The ternary hydride Rb₃ReH₁₀ can be synthesised by reacting rubidium hydride with rhenium in a hydrogen atmosphere under a pressure of above 4000 bar in a temperature range between 700 and 870 K. X-ray investigations on powder samples and elastic neutron diffraction experiments on the deuterated compound led to the crystal structure. According to the formula [ReD₉]DRb₃ the atomic arrangement of the room temperature modification corresponds to that of the perowskite structure type. The coordination polyhedron of the hydrogen atoms that surround each rhenium atom can be described crystallographically as a statistical occupation of two 24-fold positions with hydrogen. In the orthorhombic low-temperature modification the deuterium ligands are arranged in ordered positions. They form monocapped square antiprisms. Magnetic susceptibility measurements revealed Rb₃ReD₁₀ to be diamagnetic.     

Neue Oxocadmate der Alkalimetalle: K6[CdO4],Rb6[CdO4], Rb2CdO2 und Rb2Cd2O3

The crystal structure of K₆[CdO₄] and Rb₂CdO₂ has been determined from single crystal X-ray diffraction data and refined toR=0.058 (K₆[CdO₄]) andR=0.088 (Rb₂CdO₂). K₆[CdO₄] crystallizes hexagonal, space group P6₃mc with lattice constantsa=867.42 (6),c=665.5 (1) pm,c/a=0.767 andZ=2. It is isotypic with Na₆[ZnO₄]. Rb₂CdO₂ is orthorhombic, space group Pbcn witha=1045.0 (2),b=629.1 (1),c=618.3 (1) pm,Z=4, and crystallizes with the K₂CdO₂ structure type. The crystal structures can be deduced from the motif of a closest packed arrangement of O^2– with hexagonal (K₆[CdO₄]) or cubic (Rb₂CdO₂) stacking. The tetrahedra occupied by Cd²⁺ are isolated (K₆[CdO₄]) or edge-shared (formation of infinite SiS₂-like chains [CdO_4/2]) (Rb₂CdO₂). The powder diffraction pattern of Rb₆[CdO₄] [a=906.6 (1),c=694.3 (1) pm] and Rb₂Cd₂O₃ [a=642.6 (2),b=679.0 (1),c=667.9 (2) pm, =115.2 (1)] confirm isotypie with K₆[CdO₄] and K₂Cd₂O₃ respectively.

Herrn Prof. Dr.Gutman zum 65. Geburtstag gewidmet.     

Korrektur zur Kristallstruktur von „Cs4PbO3”︁ und die Strukturverwandtschaft zwischen den Modifikationen von Cs4PbO4

Correction of the Crystal Structure of “Cs₄PbO₃” and the Structural Relationship between the Modifications of Cs₄PbO₄ The compound that has been described as Cs₄PbO₃ really is Cs₄PbO₄. It does not crystallize in the space group P2₁, as assumed, but in P2₁/c. The observed fictitiuous violation of the extinction law for the c glide plane is due to twinning. The structure was refined using the original data as well as new data from an untwinned crystal. The denomination β-Cs₄PbO₄ is used to distinguish this structure from another known modification (α-Cs₄PbO₄). Both structures, α-Cs₄PbO₄ and β-Cs₄PbO₄, can be derived from the sphere packing of γ-plutonium when certain voids in its packing are occupied with oxygen atoms.     

Goldreiche Auride mit Caesium: Cs1,34Rb0,66RbAu7 und Cs1,60Rb0,40RbAu7

Gold-rich Aurides with Caesium: Cs_1.34Rb_0.66RbAu₇ and Cs_1.60Rb_0.40RbAu₇ Cs_1,60Rb_0,40RbAu₇, Raumgruppe Cmmm, Z = 2, a = 5,677(1) Å, b = 13,273(3) Å, c = 7,288(1) Å, R1/wR2 = 0,0392/0,0892, Z(F) ≥ 2σ(F) = 700 and Z(Var.) = 23. Silver coloured, brittle single crystals of Cs_1.34Rb_0.66RbAu₇ and Cs_1.60Rb_0.40RbAu₇ were obtained by the reaction of CsN₃, RbN₃ and gold sponge at 903 K. The structures were determined from X-ray single-crystal diffractometry data: Cs_1.34Rb_0.66RbAu₇, space group Cmmm, Z = 2, a = 5.657(1) Å, b = 13.265(4) Å, c = 7.281(2) Å, R1/wR2 = 0.0373/0,0628, N(F) ≥ 2σ(F) = 818 and N(var.) = 23.     

Zur Kristallstruktur von CaFeF5

On the Crystal Structure of CaFeF₅ Single crystals of CaFeF₅ were obtained by heating a mixture of the component fluorides at 860°C for 12 d (a = 549.2(1), b = 1007.6(2), c = 759.9(2) pm, β = 110.02(3)°; space group P2₁/c, Z = 4). The X‐ray structure redetermination of a twinned specimen confirmed the chain structure of octahedra sharing trans corners already known. But the anomalies reported earlier were removed and less distorted [FeF₆] octahedra and [CaF₇] pentagonal bipyramids were found, the distances of which are split within the usual range around mean values of Fe—F: 192.4 and Ca—F: 233.1 pm.     

Zur Darstellung und Kristallstruktur von Rb2Sb4S7

On the Preparation and Crystal Structure of Rb₂Sb₄S₇ Rb₂Sb₄S₇ was prepared by methanolothermal reaction of Rb₂CO₃ with Sb₂S₃ at a temperature of 140°C. An X-ray structural analysis demonstrated that the compound contains polythioantimonate(III) anions (Sb₄S₇^2?)_n, for which the basic element is a ψ-trigonal (SbS₄)-bipyramid. Edge bridged SbS₄ polyhedra build vierer single chains (Sb₄S₈^4?)_n, which are linked via two symmetry related S atoms with neighbouring chains so that an (Sb₄S₇^2?)_n sheet is formed.     

Spektralphotometrische Bestimmung von Rubidium und Caesium

Ohne Zusammenfassung

---

Spectrophotometric determination of rubidium and caesium

     

Ternäre Alkalimetall‐Übergangsmetall‐Acetylide der Zusammensetzung A2MC2 mit A = Rb,Cs und M = Pd,Pt

Ternary Alkali Metal Transition Metal Acetylides A₂MC₂ with A = Rb, Cs, and M = Pd, Pt By the reaction of Rb₂C₂ and Cs₂C₂ with palladium or platinum powder in sealed glass ampoules at 653 K ternary acetylides A₂MC₂ (A = Rb, Cs; M = Pd, Pt) were obtained. Their crystal structures were solved and refined by means of X‐ray powder investigations (Na₂PdC₂ structure type, P 3 m1, Z = 1). The crystal structures are characterised by [M(C₂)_2/2^2–] chains separated by the alkali metals. Raman spectroscopic investigations revealed wave numbers of the C–C stretching vibrations between 1833 and 1842 cm^–1, which are in good agreement with the results of the analogous sodium and potassium compounds.     

Darstellung und Kristallstruktur von Rb2Ni3Se4

Preparation and Crystal Structure of Rb₂Ni₃Se₄ The compound Rb₂Ni₃Se₄ was synthesized by heating a mixture of rubidium carbonate, nickel and selenium at 850°C in an atmosphere of hydrogen. The compound has a golden lustre and crystallizes with the K₂Pd₃S₄-type structure; a = 10.555(3) Å, b = 27.588(6) Å, c = 6.031(6) Å, Z = 8, Fddd (No. 70). The structure can be described as a stacking of layers of the composition Rb₂Ni₃Se₄ with a stacking sequence abcd. The electrostatic part of lattice energy (MAPLE) will be discussed for compounds of the compositions A₂M₃X₄ (A K, Rb, Cs; M Ni, Pd, Pt and X S, Se).     

Synthese und Kristallstruktur von K2Mn3S4

Synthesis and Crystal Structure of K₂Mn₃S₄ Single crystals of K₂Mn₃S₄ have been prepared by a fusion reaction of potassium carbonate with manganese in a stream of hydrogen sulfide at 900 °C. K₂Mn₃S₄ crystallizes in a new monoclinic layered structure type (P2/c, a = 7.244(2) Å, b = 5.822(1) Å, c = 11.018(5) Å, β = 112.33(3)°, Z = 2) which can be described as a stacking variant of the orthorhombic Cs₂Mn₃S₄ structure type. Measurements of the magnetic susceptibilities show antiferro‐magnetic interactions.     

Kristallstruktur von RbKS

Crystal Structure of RbKS The colourless compound RbKS has been prepared for the first time by annealing a mixture of K₂S and Rb₂S. Very hygroscopic RbKS crystallizes in the orthorhombic space group Pnma with the lattice parameters a = 822.2(3), b = 504.3(4), c = 945.2(2)pm, Z = 4 in the anti-PbC1₂ structure type.     

Synthese und Kristallstruktur von Sr2Rh7P6

Synthesis and Crystal Structure of Sr₂Rh₇P₆ Single crystals of Sr₂Rh₇P₆ were obtained by reaction of the elements in molten lead at 1100 °C and investigated by X-ray methods. The compound crystallizes tetragonally (a = 11.080(2), c = 4.098(1) Å) and forms a crystal structure (P 4 2₁m; Z = 2) with ThCr₂Si₂ analogous units, which are linked with each other in a new way. Therefore the RhP₄ tetrahedra form bands of edge sharing chains parallel to [001] anstead of layers as in the ThCr₂Si₂ type structure. The arrangement enables a part of the P atoms to form short P–P distances of 2,26 Å and space for additional Rh atoms with a likewise distorted tetrahedral coordination of P atoms is obtained.     

Ein neuer Zugang zu Alkalivanadaten(IV,V) Die Kristallstruktur von Rb2V3O8

A New Access to Alkali Vanadates(IV,V) Crystal Structure of Rb₂V₃O₈ By heating vanadium(V) oxide with rubidium iodide to 500°C, the vanadium experiences partial reduction and Rb₂V₃O₈ is obtained. It has the fresnoite structure. Crystal data: a = 892.29(7), c = 554.49(9) pm at 20°C, tetragonal, space group P4bm, Z = 2. X-ray crystal structure determination with 620 observed reflexions, R = 0.027. V₂O₇ units share vertices with VO₅ square pyramids, forming layers; a layer can be regarded as association product of VO²⁺ and V₂O₇^4? ions. The Rb⁺ ions between the layers have pentagonal-antiprismatic coordination.     

Zur Kenntnis der Kristallstruktur von Melem C6N7(NH2)3

On the Crystal Structure of Melem C₆N₇(NH₂)₃ Single crystals of melem ( 1 ) were grown from both DMSO‐solutions and the gas phase. The structure of melem ( 1 ) was solved by single‐crystal X‐ray diffraction (P2₁/c, Z = 4, a = 741.66(15), b = 862.28(17), c = 1335.9(3) pm, β = 99.91(3)° R1 = 0.037 for 1098 reflections). The structure determination by X‐ray powder diffraction, which has been previously conducted, is in agreement with our data. The increased quality of the structural information allows for a more detailed understanding of the hydrogen bonding network.     

Zur Kristallstruktur von W2C

Ohne ZusammenfassungMit 1 Abbildung     

Über eine neue Modifikation des Na2C2

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.     

Die Kristallstruktur von Cs2S. mit einer Bemerkung über Cs2Se,Cs2Te,Rb2Se und Rb2Te

The Crystal Structure of Cs₂S and a Remark about Cs₂Se, Cs₂Te, Rb₂Se, and Rb₂Te Cs₂S crystallizes orthorhombic, a = 8.57₁, b = 5.38₃, c = 10.3₉ Å, Z = 4, d_rö = 4.13, d_pyk = 4.19 g · cm^?3, D–Pnma with \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {{\rm Cs}}\limits^|,\mathop {{\rm Cs}}\limits^\parallel $\end{document} and S in 4(c) each, for parameter see text. It is R = 10,4% for 202 of 222 possible reflexes. There is a sequence of S^2? corresponding to the hexagonal closest packing of sphares. Cs occupies half of “tetrahedron” and all “octahedron vacancies”; the deviation of \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {{\rm Cs}}\limits^|, $\end{document} in ?oktahedron vacancies”? is noticeable. Effective Coordination Numbers, ECoN, and the Madelung Part of Lattice Energy, MAPLE, are calculated and discussed.     

Synthese und Kristallstruktur von Bi2ErO4I

Synthesis and Crystal Structure of Bi₂ErO₄I Bi₂ErO₄I was prepared by solid‐state reaction of stoichiometric mixture of BiOI, Bi₂O₃ and Er₂O₃. Bi₂ErO₄I is a new compound and the first bismuth rare earth oxide iodide. The crystal structure was determined by the Rietveldmethod (P4/mmm, a = 3,8896(6) Å, c = 9,554(2) Å, Z = 1). In this structure [M₃O₄]⁺‐layers are interleaved by single I^–‐layers. Er and Bi atoms of Bi₂ErO₄I are 8‐coordinated. The structure can be derived from the LiBi₃O₄Cl₂‐structure type.     

Zur Kristallstruktur von MnF3 und MnPtF6

On the Crystal Structure of MnF₃ and MnPtF₆ Single crystal investigations of MnF₃ (rubyred) confirmed the crystal structure based on powder data [2]: monoclinic, space group C 2/c?C (No. 15) with a = 892.02 pm, b = 504.72 pm, c = 1 347.48 pm, β = 92.64° with Z = 12. The corresponding determination of the crystal structure of MnPtF₆, yellow, confirmed the unit cell [3] with a = 510.47 pm, c = 1 421.0 pm and γ = 120°, Z = 3 space group R 3 -C (No. 148). For both compounds detailed parameters respectively interatomic distances have been obtained.     

Zur Kristallstruktur von α-TlSmW2O8

Single crystals of -TlSm(WO₄)₂ were examined by X-ray diffractometer technique (space group C _2h ⁶ -C2/c;a=10.770,b=10.597,c=7.597 Å, =130.09°,Z=4). The coordination of W⁶⁺, Sm³⁺ and Tl⁺ are discribed and discussed.-TlSm(WO₄)₂ is isotypic to -KY(WO₄)₂.