Einkristallstrukturbestimmungen der kubischen Hochdruckelpasolithe Rb2LiFeF6 und Cs2NaFeF6: Druck-Abstands-Paradoxon ohne Änderung der Koordinationszahl

Single Crystal Structure Determinations of the Cubic High Pressure Elpasolites Rb₂LiFeF₆ and Cs₂NaFeF₆: Pressure-Distance Paradox without Change of Coordination Number At single crystals of metastable high pressure phases of Rb₂LiFeF₆ (a = 824.4 pm) and Cs₂NaFeF₆ (a = 873,9 pm) the parameters of the cubic elpasolite structure (Fm3 m, Z = 4) were determined by X-ray methods. Compared to the 12L-structures of the normal pressure phases (R3 m, hex. Z = 6) only the distances within the 12-coordination, Rb? F = 291.7 resp. Cs? F = 309.9 pm, are compressed by 2–3%. However, the octahedral distances Fe? F = 194.6 pm and Li? F = 217.6 pm resp. Fe? F = 194.9 pm and Na? F = 242.0 pm, are enlarged by 1–4%, though there was no increase in coordination number. This paradoxical behaviour is discussed. Difference Fourier syntheses reveal disorder only for the lithium positions in Rb₂LiFeF₆, which are 30 pm off-center, corresponding to a splitting of distances Li? F into 188, 247 and 4 × 220 pm.     

Strukturen caesiumhaltiger Fluoride. VII. Cs6Ni5F16 – eine neue Verbindung im System CsF/NiF2 und ihre Kristallstruktur

Structures of Caesium-containing Fluorides. VII. Cs₆Ni₅F₁₆ – a New Compound in the System CsF/NiF₂ and its Crystal Structure Single crystals of a more caesium-containing phase of composition Cs₆Ni₅F₁₆, forming in the course of solid state CsNiF₃ preparation, could be isolated and their structure determined: a = 618.4(1), b = 1. 455.5(2), c = 2145.1(2) pm, space group Cmca, Z = 4, R = 0.030 (1936 independent reflections). The structure contains chains of five face-sharing octahedra, which are connected at their ends via corners to form a zig-zag layer. The Ni? Ni distances within the chains are 264.1 and 270.2 pm, the average Ni? F distance is 202.0 pm. The caesium atoms exhibit 10-, 11-, and 12-coordination. The structural relations to 2L? CsNiF₃ and Cs₄Ni₃F₁₀ are discussed.     

Darstellung,Struktur und Schwingungsspektren der Oxofluorowolframate(VI) Cs2[WO3F2] und Cs3[W2O4F7]

Synthesis, Structure, and Vibrational Spectra of the Oxofluorotungstates(VI) Cs₂[WO₃F₂] and Cs₃[W₂O₄F₇] Cs₂[WO₃F₂] crystallizes from a melt with the same composition. The orthorhombic unit cell with a = 6.779(2), b = 7.668(1) and c = 11.626(3) Å, space group Pn2₁a, contains 4 formula units. The WO₃F₂^2? anion is polymer, W octahedrally coordinated according to the results of the X-ray crystal structure determination. Planar dioxodifluoro groups are linked into chains by oxygen atoms. The lengths of the W? O bonds are alternating. Cs₃[W₂O₄F₇] crystallizes trigonal, space group P3 m1, with a = 21.118(4) and c = 8.434(2) Å, Z = 9. The structure consists of two sets of crystallographically non equivalent dimeric anions with the formula [O₂F₃W? F? WO₂F₃]^3?. Part of the ligand atoms are disordered. The vibrational spectra of both compounds show the presence of cis-dioxo groups of the terminal ligands.     

Überschreitungen der konventionellen Zahl von Clusterelektronen in Metallhalogeniden des M6X12‐Typs: W6Cl18, (Me4N)2[W6Cl18] und Cs2[W6Cl18]

Beyond the Conventional Number of Electrons in M₆X₁₂ Type Metal Halide Clusters: W₆Cl₁₈, (Me₄N)₂[W₆Cl₁₈], and Cs₂[W₆Cl₁₈] Black octahedral single crystals of W₆Cl₁₈ were obtained by reducing WCl₄ with graphite in a silica tube at 600 °C. The single crystal structure refinement (space group R 3¯, Z = 3, a = b = 1498.9(1) pm, c = 845.47(5) pm) yielded the W₆Cl₁₈ structure, already reported on the basis of X‐ray powder data. (Me₄N)₂[W₆Cl₁₈] and Cs₂[W₆Cl₁₈] were obtained from methanolic solutions of W₆Cl₁₈ with Me₄NCl and CsCl, respectively. The structure of (Me₄N)₂[W₆Cl₁₈] was refined from X‐ray single crystal data (space group P 3¯m1, Z = 1, a = b = 1079.3(1) pm, c = 857.81(7) pm), and the structure of Cs₂[W₆Cl₁₈] was refined from X‐ray powder data (space group P 3¯, Z = 1, a = b = 932.10(7) pm, c = 853.02(6) pm). The crystal structure of W₆Cl₁₈ contains molecular W₆Cl₁₈ units arranged as in a cubic closest packing. The structures of (Me₄N)₂[W₆Cl₁₈] and Cs₂[W₆Cl₁₈] can be considered as derivatives of the W₆Cl₁₈ structure in which 2/3 of the W₆Cl₁₈ molecules are substituted by Me₄N⁺ ions and Cs⁺ ions, respectively. The conventional number of 16 electrons/cluster is exceeded in these compounds, with 18 electrons for W₆Cl₁₈ and 20 electrons for (Me₄N)₂[W₆Cl₁₈] and Cs₂[W₆Cl₁₈]. Cs₂[W₆Cl₁₈] exhibits temperature independent paramagnetic behaviour.     

Strukturen caesiumhaltiger Fluoride. V. Die pseudohexagonale Wolframbronzestruktur der monoklinen Phase Cs0,4Zn0,4Fe1,6F6 und verwandter Cäsium-Übergangsmetallfluoride

Structures of Cesium-containing Fluorides. V. Pseudohexagonal Tungsten Bronze Structure of the Monoclinic Phase Cs_0.4Zn_0.4Fe_1.6F₆ and Related Cesium Transition Metal Fluorides The crystal structure of the pseudohexagonale phase Cs_0.4Zn_0.4Fe_1.6F₆ was refined in the monoclinic space group P2₁ (a = 747.4, b = 763.6, c = 746.1 pm, β = 120.0°, z = 3). Using 1067 single crystal reflections R = 6.3% was reached. Compared to the hexagonal tungsten bronze structure the corner-sharing of octahedra shows pronounced angles also along the unique axis (M? F? M = 159.0°). The average bridge angle in the framework of tilted octahedra is 149.6°. Structural relations are discussed.     

Das erste zweikernige Oxoferrat(II): „Cs2K4[O2FeOFeO2]”︁

The First Binuclear Oxoferrate(II): ?Cs₂K₄[O₂FeOFeO₂]”? For the first time ?Cs₂K₄[Fe₂O₅]”? was obtained by annealing intimate mixtures of Cs₂O, K₂O, and CsFeO₂ (molar ratio Cs : K : CsFeO₂ 1.3 : 2.1 : 1) in a closed Fe-cylinder (74 d; 470°C) in the form of red single crystals. The structure determination (four-circle diffractometer, MoKα , 760 out of 857 I_o(h kl); R = 5.8%, R_w = 4.6%) confirms the space group C2/m; a = 707.4, b = 1138.5, c = 699.7 pm, β = 91.76°, Z = 2. Essential part of the structure is the binuclear, planar [O(1)₂Fe? O(2)? FeO(1)₂]^6? group which is for the first time observed with oxoferrates(II). Despite different space groups the crystal structure is related to that of Rb₂Na₄[Co₂O₅].     

Die Kristallstruktur von Na2NiAlF7—ein Beitrag zum Problem der wahren Raumgruppe orthorhombischer Weberite

The Crystal Structure of Na₂NiAlF₇ — a Contribution to the Problem of the True Space Group of Orthorhombic Weberites The X-ray single crystal structure determination of the orthorhombic weberite Na₂NiAlF₇ (a = 707.4(2), b = 1003.8(2), c = 731.5(1) pm; Z = 4) was performed in space group Imma, after all reflections hk0 with h(k) = 2n + 1 could be eliminated, as they proved simulated by Renninger effect and/or λ/2 reflections. The alternative space groups Imm2 resp. I2₁2₁2₁ of former weberite structure determinations thus became obsolete. The refinement using 880 independent reflections ended at wR = 0.0232. The resulting average distances within the framework of octahedra are Ni? F = 197.3, Al? F = 180.4 pm.     

Neue Fluorperowskite mit Cr‴ und Mn‴: A(B03Cr0.5)F3 und A(B05Mn0,5)F3; A,B=Alkalimetall

New fluoroperovskites with Cr^III and Mn^III: A(B_0.5Cr_0.5)F₃ and A(B_0.5Mn_0.5)F₃; A, B = alkali We obtained Cs₂KCrF₆ (a = 9.00₄ Å), Rb₂KCrF₆ (a = 8.81₇ Å), Rb₂NaCrF_e(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.     

Darstellung und Kristallstruktur der bekannten Zintl‐Phasen Cs3Sb7 und Cs4Sb2

Synthesis and Crystal Structure of the known Zintl Phases Cs₃Sb₇ and Cs₄Sb₂ Cs₃Sb₇ and Cs₄Sb₂ were synthesized from the elements and their crystal structures were determined on the basis of single crystal x‐ray data. Cs₃Sb₇ crystallizes in the monoclinic system with space group P2₁/c (a = 1605.7(1) pm, b = 1571.1(1) pm, c = 2793.9(2) pm, β = 96.300(2)°, Z = 16) and contains anions Sb₇^3–. In the structure of Cs₄Sb₂ (orthorhombic, space group Pnma, a = 1598.5(3) pm, b = 631.9(2) pm, c = 1099.5(2) pm, Z = 4) dumbbells Sb₂^4– are present.     

Die Antimonid–Triantimonidometallate(III) Cs6K3Sb[AlSb3] und Cs6K3Sb[GaSb3]

The Antimonide Triantimonidometallates(III) Cs₆K₃Sb[AlSb₃] and Cs₆K₃Sb[GaSb₃] The novel compounds Cs₆K₃Sb[AlSb₃] and Cs₆K₃Sb[GaSb₃] are formed from stoichiometric mixtures of Cs, AlSb (GaSb) and KSb in sealed niobium ampoules at 950 K. The hexagonal structures are especially characterized by one-dimensional rod packings ¹∞[Cs₆K₃Sb] which are formed from columns of condensed (Cs₆K_6/2) icosahedra. The icosahedra are centered by Sb^3-? anions. The trigonal planar anions [AlSb₃]^6-? and [GaSb₃]^6-? are embedded between the icosahedra columns, and they are coordinated by alkali metal atoms. The FIR spectra were assigned to the vibrations of the [MSb₃]^6-? anions, with respect to the 6 m2-D_3h symmetry. (P6₃/mmc, No. 194; a = 1101.7 and 1097.2 pm; c = 1158.9 and 1150.1 pm; Z = 2; Single crystal data: 574 and 546 reflections; R = 0.073 and 0.029. Distances:d(Al? Sb) = 265.4 pm; d(Ga? Sb) = 265.1 pm; d(Sb? Cs) = 401.6–423.0 pm; d(Sb? K) = 358.6–367.3 pm).     

Kristallstruktur des „supramolekularen”︁ Komplexes [Cs2(18-Krone-6)][HgI4] mit ungewöhnlich koordinierten Cs-Ionen

Crystal Structure of the “Supramolecular” Complex [Cs₂(18-crown-6)][HgI₄] with Unusually Coordinated Cs Ions The reaction of 18-crown-6, 1,4,7,10,13,16-hexaoxacyclooctadecane, with HgI₂/CsI in methanol yields crystals of [Cs₂(C₁₂H₂₄O₆)][HgI₄]. The compound crystallizes monoclinically, space group P2₁/c, Z = 4, a = 1574.8(3), b = 1067.0(3), c = 1693.2(6) pm, and β = 98.29(3)º. The structure consists of a network made up of two different types of [Cs-(18-crown-6)-Cs]²⁺ cations, interconnected by [HgI₄]^2? anions. The cations form an “anti-sandwich” structure with relatively short Cs ? Cs distances of 382 pm in the first type of cations and a longer distance of 480 pm in the second type of cations.     

Cs6[TeMo6O24] · 2 Te(OH)6 · 4 H2O ? eine Tellursäure-reiche Einschlußverbindung

Cs₆[TeMo₆O₂₄] · 2 Te(OH)₆ · 4 H₂O – A Telluric Acid-rich Inclusion Compound Single crystals of Cs₆[TeMo₆O₂₄] · 2 Te(OH)₆ · 4 H₂O have been grown from aqueous solution. It crystallizes triclinically in space group P1 with Z = 1, a = 1 086.6(1), b = 1 095.6(1), c = 1 105.5(1) pm, α = 118.83(1), β = 106.22(1) and γ = 100.00(1)°. X-ray structure determination (5 755 reflections, 251 parameters, R_g = 0.0355) revealed an infinite chain consisting of hydrogen bonded (OH …? O 259.4(5) – 267.4(6) pm) Te(OH)₆ molecules and [TeMo₆O₂₄]^6? anions to be the Prominent structural feature. Further hydrogen bonds between neighbouring Te(OH)₆ molecules connect these chains to yield a two-dimensionally infinite arrangement.     

Strukturen caesiumhaltiger Fluoride. VIII. Cs7Ni4F15 und Cs7Co4F15: Die Kristallstrukturbestimmung an den bisher caesiumreichsten Verbindungen in den zugehörigen Systemen CsF/MF2

Structures of Cesium-containing Fluorides. VIII. Cs₇Ni₄F₁₅ and Cs₇Co₄F₁₅: Crystal Structure Determination of the Hitherto Cesium-richest Compounds in the Corresponding Systems CsF/MF₂ . The only nickel-containing phase we could identify after solid state reaction 2 CsF + NiF₂ was the compound Cs₇Ni₄F₁₅. The single crystal structure determination of this monoclinic fluoride (and its cobalt analog Cs₇Co₄F₁₅) yielded a = 787.2 (788.3), b = 1089.7 (1096.6), c = 1149.5 (1164.9) pm, β = 92.74 (92.59)°, space group P2₁/c, Z = 2, R_g = 0.045 (0.058) for 2543 (2716) independent reflections. The resulting strongly puckered layer structure rather than of single octahedra consists of face-sharing M₂F₉ units, which are connected via the half of their remaining corners. The M? F distances vary from 195.1 to 212.0 (196.7 to 217.0) pm and show unusual high mean values of 203.7 (206.5) pm. Data for comparison and further details are discussed.     

Synthese und Kristallstrukturen der Polytelluridokomplexe (PPh4)4[M2Te12] von Kupfer(I) und Silber(I)

Syntheses and Crystal Structures of the Polytellurido Complexes (PPh₄)₄[M₂Te₁₂] of Copper(I) and Silver(I) The title compounds have been prepared as black crystal needles by reactions of Na₂Te₃ with CuCl and AgNO₃, respectively, in dimethylformamide in the presence of PPh₄Br. With regard to the large cell dimensions the crystal structure determinations were done by an imaging plate instrument. (PPh₄)₄[Cu₂Te₁₂]: Space group P2₁/n, Z = 6, 51 338 detected reflections, structure determination with 14 177 unique reflections with I > 4σ(I), R = 0.081. Lattice dimensions at ? 50°C: a = 1 704.5, b = 1 694.5, c = 5 044 pm, β = 94.20°. (PPh₄)₄[Ag₂Te₁₂]: Space group P2₁/n, Z = 6, 80 811 detected reflections, structure determination with 16 092 unique reflections with I > 3σ(I), R = 0.052. Lattice dimensions at ? 50°C: a = 1 703.8, b = 1 722.9, c = 5 123 pm, β = 94.65°. The structures of the isotypic compounds consist of six symmetry independent PPh₄⁺ ions and two symmetry independent anions [M₂Te₁₂]^4?, in which the metal atoms of two (MTe₄)^?-fivering fragments are linked by a Te₄^2? chain.     

Über Cs2TlBr5 – ein Pentabromothallat (III) mit tetraedrischen TlBr4− - und oktaedrischen TlBr63− -Anionen

On Cs₂TlBr₅ — a Pentabromothallat (III) with Tetrahedral TlBr₄^? and Octahedral TlBr₆^3? Anions Cs₂TlBr₅ has been synthesized by crystallization from aqueous TlBr₃/CsBr solutions. The orthorhombic structure (a = 1330.2(11); b = 777.0(3); c = 2349.3(6) pm; Z = 8, space group Pnma-Nr. 62) contains isolated tetrahedral TlBr₄- and octahedral TlBr₆^3? anions which are packed together with the Cs⁺ cations in an anti-CaWO₄ arrangement. At 260°C Cs₂TlBr₅ decomposes irreversibly to Cs₃Tl₂Br₉ and CsBr.     

Über Chalkogenolate. 152. Untersuchungen über Derivate der N-Thioformyldithiocarbamidsäure. 2. Kristallstruktur von Tetra-n-butylammonium-N-thioformyldithiocarbamat

On Chalcogenolates. 152. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 2. Crystal Structure of Tetra-n-butylammonium N-Thioformyl Dithiocarbamate The title compound [N(ⁿC₄H₉)₄][S₂C? NH? CS? H] crystallizes with Z = 2 in the triclinic space group P1 with cell dimensions a = 9.694(2) Å, b = 11.478(3) Å, c = 12.551(6) Å, α = 63.03(3)°, β = 66.42(2)°, γ = 85.60(2)°. The crystal structure has been determined from single crystal X-ray data measured at 20°C and refined to a conventional R of 0.061 for 2249 independent reflections (R_w = 0.042). The structure is built up of dimeric aggregates consisting of 2[N(ⁿC₄H₉)₄]⁺ cations and 2[S₂C? NH? CS? H]^? anions. The two anions are linked together by ? CS? S…?H? N bridges. To make possible a space saving stacking of the dimeric aggregates in the crystal, one methyl group in terminal position of one n-butyl chain in the cation has gauche conformation.     

Strukturen cäsiumhaltiger Fluoride,III. Die Kristallstrukturen der hexagonalen Elpasolithe: 12 L-Cs2NaCrF6, 12 L-Cs2NaFeF6 und 2 L-Cs2LiGaF6

The results of complete X-ray single-crystal structure determinations of the isostructural compounds Cs₂NaCrF₆ and Cs₂NaFeF₆, crystallizing in a 12 L-structure in space group $\text{R}\text{3}\text{m}$, as well as of 2 L-Cs₂LiGaF₆ (space group $\text{P}\text{3}\text{m1}$), are reported. The structures, which contain face sharing octahedra, are discussed in comparison to the hexagonal fluoroperovskites. The mean distances observed, CrF = 1.910 Å, FeF = 1.926 Å, GaF = 1.93 Å, are compared to recently published data.     

Hochdrucksynthese und Struktur von Rb2PtH6 und Cs2PtH6, ternären Hydriden mit K2PtCl6-Struktur

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).