Über neue Fluoride des Kupfers Zur Kenntnis von Cs[CuF4]

New Fluorides of Copper. On Cs[CuF₄] Due to powder diagrams, Cs[CuF₄], the first diamagnetic fluoride (χ_Mol = ?516·10^?6 cm³/Mol) of trivalent copper, with planar coordination orange-coloured, crystallizes tetragonal, K[BrF₄]-type of structure with planar [CuF₄]-units (a = 5.8488(4) Å, c = 12.043(1) Å). We obtained Cs[CuF₄] by high pressure fluorination (p_F2 = 350 bar, 400°C, 7 h) of CsCuCl₃ in autoclaves.     

The Ternary System BaF2/CuF2/AlF3 and the Crystal Structure of Ba45Cu28Al17F197

The ternary system BaF₂/CuF₂/AlF₃ is investigated by X‐ray diffraction techniques and an isothermal section at 620 °C is established. It exhibits ten quaternary phases and among them Ba₄₅Cu₂₈Al₁₇F₁₉₇. This fluoride has a triclinic cell: a = 14.024(1) Å, b = 23.778(1) Å, c = 25.480(1) Å, α = 90.44(1)°, β = 90.26(1)°, γ = 107.03(1)°, Z = 2. Its crystal structure was solved in the space group P1 (n^o1), from X‐ray single crystal data using 41976 unique reflections. It is built up from a complex arrangement of aluminium and copper fluorine polyhedra, which are regular [AlF₆] and strongly distorted [CuF₆] octahedra, [CuF₆] trigonal prisms and [Cu₂F₁₀] bipolyhedral units constituted either by two octahedra, or one octahedron and one trigonal prism, connected by an edge. These polyhedra are organized in planes of about two octahedra thickness, which form a succession of sheets running perpendicularly to the [100] direction of the cell. Each sheet is constituted by infinite chains of distorted polyhedra connected by edges and vertices and linked together by the vertices of blocks of four and six polyhedra, involving aluminium fluorine octahedra and copper fluorine bipolyhedral units or octahedra. The barium ions, 10 to 14‐coordinated to fluorine atoms, ensure the electroneutrality of the structure. They are inserted inside the planes.     

Complex copper(II) fluorides. XIII. Ternary system BaF2?CuF2?GaF3 and Crystal Structure of Ba3CuGa2F14

The ternary system BaF₂? CuF₂? GaF₃ is investigated by X-ray diffraction experiments. It exhibits seven quaternary phases: six of which correspond to types previously evidenced in other BaF₂? CuF₂? MF₃ systems (three “polytypic” phases obtained by adding small amounts of GaF₃ to BaCuF₄, a tetragonal non-stoichiometric phase: Ba_3+x Ga_2?2xCu_2xF₁₂ and two stoichiometric fluorides: triclinic Ba₂CuGa₂F₁₂ and monoclinic Ba₁₀Cu₁₂GaF₄₇); the seventh compound Ba₃CuGa₂F₁₄ hitherto unknown, corresponds to a new structural type. It is monoclinic (pseudo-orthorhombic) space group P2₁/n with a = 7.402(3) Å, b = 27.88(1) Å, c = 5.521(2) Å, β = 90.12(3)°, Z = 4. The structure was solved from single crystal data using 5133 independent reflections (R = 0.047, R_w = 0.051). It is built up from infinite cis-chains of GaF₆ octahedra linked by monocapped trigonal prisms CuF₇.     

Détermination de la structure cristalline du ferrite de baryum Ba2Fe6O11

The crystal structure of dibarium triferrite Ba₂Fe₆O₁₁ has been solved by direct methods, using intensity data collected by means of an automated diffractometer (MoKα radiation) and corrected for absorption. It crystallizes in the orthorhombic space group Pnnm: a = 23.024(10)Å, b = 5.181(3) Å, c = 8.900(4) Å, Z = 4. Program MULTAN was successfully used for locating Ba²⁺ and most of the Fe³⁺ ions. The structure was further refined by conventional Fourier and least-squares methods (full-matrix program) to a final R value of 0.045 for 1448 observed reflections. Fe³⁺ ions occur in both octahedral (FeO mean distance: 2.02 Å) and tetrahedral (FeO mean distance: 1.865 Å) coordination. Two types of Ba²⁺ ions are found, with six and seven neighboring oxygen atoms. The structure consists of sheets of edge-shared FeO₆ octahedra which are connected by means of corner-shared tetrahedra.     

Pb3Fe2F12: A new fluorometallate with a tetrameric structural unit

Pb₃Fe₂F₁₂ grown by hydrothermal synthesis, crystallizes in the triclinic system, space group P1 , with a = 7.403(2) Å, b = 7.621(2) Å, c = 9.890(3) Å, α = 110.45(2)°, β = 107.98(1)°, γ = 95.92(2)°, V = 483.12(4) ų, Z = 2. The structure was solved from single crystal data using 3 913 independent reflections (R = 0.045 and R_w = 0.045). Characteristical of this structure is the presence of isolated tetrameric groups [Fe₄F₂₀]^8? in form of “rings” as previously observed in Ba₃Al₂F₁₂. “Independent” fluorine ions are also located and their cationic coordination is discussed. In contrast to Ba₃Fe₂F₁₂, all the rings are parallel in the structure.     

A structural model for barium platinum oxide,Ba3Pt2O7

A single crystal study of Ba₃Pt₂O₇ shows that the structure tolerates a variable composition which can be written Ba₃Pt_2+xO_7+2x. The crystal studied has a hexagonal cell of dimensions a = 10.108 ± 0.006 Å and c = 8.638 ± 0.009 Å, and a probable space group $\text{P}\text{6}\text{2c, Z = 4}$. The density determined by water displacement is 7.99 g/cm³; the theoretical density for Ba₃Pt₂O₇ is 7.94 g/cm³. The structure was determined from the set of 401 observed independent reflections obtained from 5189 reflections measured by automated counter methods. Refinement on F was carried to a conventional R of 8.0%. The structure has barium-oxygen layers with an essentially four-layer stacking sequence of the double hexagonal (ABAB) type. Platinum is found mainly in face-sharing octahedra, but is also distributed over some sites in which the coordination is nearly square planar and other sites in which the coordination is trigonal prismatic with three PtO bond lengths of 2.00 Å and three long PtO distances of 2.65 Å. The platinum with planar coordination is 0.08 Å from the plane of the four oxygen atoms.     

The Crystal Structure of Ba3Cu2Al2F16: a Relative of Ba4Cu2Al3F21

Ba₃Cu₂Al₂F₁₆ is monoclinic: a = 7.334(1)Å, b = 5.320(2)Å, c = 16.022(1)Å, β = 96.34(1)°, Z = 2. Its crystal structure was solved in the space group P2₁ (No. 4) from synchrotron X‐ray single crystal data using 2685 unique reflections (2639 with F_o/σ(F_o) > 4). The final R factor is 0.044. The structure consists of a succession along the c‐axis of the cell of three layers of two different kinds of sheets developing in the (a, b) plane. The first one, formulated [(AlF₅)₂]_∞^4— and hereafter named A, is built up from infinite cis‐chains of aluminium‐fluorine octahedra [AlF₆], linked by two vertices and distanced by a. The second one, formulated [Cu₂AlF₁₁]_∞^4— and named B, is bidimensional. It is constituted of distorted copper‐fluorine octahedra [CuF₆], linked by edges, which form infinite chains interconnected by three vertices of isolated [AlF₆] octahedra. The stacking sequence of the sheets is (A, B, B)_∞. The barium ions, 12‐coordinated, are inserted between the sheets. The crystal structure of Ba₃Cu₂Al₂F₁₆ is closely related to that of Ba₄Cu₂Al₃F₂₁. Only the proportion and the stacking sequence of the two kinds of sheets in the c‐direction differ, according to two different compositions and two different symmetries.     

The Crystal Structure of Ba2CuAlF9: a New Structure Type in Copper Fluoride Chemistry

Ba₂CuAlF₉ is monoclinic: a = 5.374(2) Å, b = 7.312(2) Å, c = 9.371(3) Å, β = 90.20(1)°, Z = 2, space group P2₁/c (n° 14). The crystal structure was solved from X-ray single crystal data using 1071 unique reflections (900 with F_o/σ(F_o) > 4, R factor = 0.075). It is built up from infinite isolated cis chains of [MF₆] mixed occupied fluorine octahedra sharing each, one edge and one vertex (M is randomly Cu or Al). An analogous kind of linkage was already observed for two other compounds from the ternary system BaF₂/CuF₂/AlF₃. Close structural relationships exist between the cationic subnetworks of γ-BaAlF₅ and Ba₂CuAlF₉.     

New Examples for the Unexpected Stability of the 10π‐Electron Hückel Arene [Si6]10–

The compounds Ba₄Ag₂Si₆, Eu₄Ag₂Si₆, and Ca₄Ag₂Si₆, prepared from the elements at 1273 K (the components in inner corundum crucibles are enclosed in sealed quartz ampoules), are brittle semiconductors with silvery luster. They react slowly with acids liberating hydrogen. Ba₄Ag₂[Si₆] and Eu₄Ag₂[Si₆] crystallize like Ba₄Li₂[Si₆] (space group Fddd (No. 70); a = 8.613 Å, b = 14.927 Å, c = 19.639 Å, and a = 8.420 Å, b = 14.585 Å, c = 17.864 Å, respectively), whereas Ca₄Ag₂[Si₆] represents a new structure type (space group Fmmm (No. 69); a = 8.315 Å, b = 14.391 Å, c = 8.646 Å). The three compounds are Zintl phases with the formal charges M²⁺, Ag⁺ and [Si₆]^10–. The mean bond lengths d(Si–Si) = 2.335–2.381 Å in the 10π‐Hückel arene [Si₆]^10– as well as d(Ag–Si) = 2.464–2.595 Å vary with the size of the M²⁺ cations. The chemical bonding was analyzed in terms of the Electron Localization Function (ELF) and compared with the bonding in related systems (Ce₄Co₂Si₆).     

Syntheses,Crystal Structures,and Properties of the Novel Thioborates KBa4(BS3)3 and K4Ba11(BS3)8S

Our systematic studies on quaternary thioborates containing both a comparably small alkali metal ion and a large alkaline earth cation lead to the two new crystalline phases KBa₄(BS₃)₃ and K₄Ba₁₁(BS₃)₈S. The former consists of isolated BS₃ units and the corresponding counter‐ions while in the latter BS₃^3– and S^2– anions coexist. In both compounds boron is found in a trigonal‐planar coordination, in the case of K₄Ba₁₁(BS₃)₈S the additional sulfide anions are located inside an octahedron built of six barium cations. The two compounds were prepared in solid state reactions from the metal sulfides, amorphous boron and sulfur. Evacuated carbon coated silica tubes were used as reaction vessels since temperatures up to 870 K were applied. KBa₄(BS₃)₃ crystallizes in the monoclinic space group C 2/c (no. 15) with a = 14.299(6) Å, b = 8.808(3) Å, c = 13.656(5) Å, β = 98.72(4)°, and Z = 4, while for K₄Ba₁₁(BS₃)₈S the trigonal space group R 3 c (no. 167) was found with a = 18.146(3) Å, c = 25.980(7) Å, and Z = 6. X‐ray powder patterns are compared to calculated diffraction data obtained from single crystal X‐ray structure determination, in the case of K₄Ba₁₁(BS₃)₈S vibrational spectra were recorded.     

Reaction of copper(II) cysteinate with thiosemicarbazide: Crystal structure of a complex of copper(II) thiocyanate with thiosemicarbazide

The reaction of copper(II) cysteinate with thiosemicarbazide (TSC) in water was found to yield complex of copper(II) thiocyanate of the [Cu(TSC)₂(SCN)₂] composition, whose crystal structure was determined by X-ray crystallography. Crystals of the complex are triclinic with a = 6.040 Å, b = 7.112 Å, c = 8.276 Å, α = 91.34°, β = 101.72°, Γ = 114.83°, Z = 2, space group \(P\bar 1\). Structural units of the complex are [Cu(TSC)₂]²⁺ centrosymmetric cations and (SCN)^? anions linked by hydrogen bonds (HB), as well as by electrostatic and π-π stacking interactions. The coordination polyhedron of Cu atoms is a square completed to bipyramid; the bonds Cu(1)-N(3), Cu(1)-S(1), and Cu(1)-S(2) are 2.002 Å, 2.303 Å, and 3.015 Å, respectively.     

Crystal structure and vapor pressure of a copper(II) complex with 2,2,6,6-tetramethyl-4-fluoroheptane-3,5-dione

Synthesis and single crystal X-ray diffraction study were carried out for copper(II) 2,2,6,6-tetramethyl-4-fluoroheptane-3,5-dionate (Bruker AXS P4 automated diffractometer, MoK _α radiation). Crystal data for C₂₂H₃₆CuF₂O₄: a = 5.9165(4) Å, b = 10.2787(7) Å, c = 10.5223(8) Å, α = 81.383(3)°, β = 76.106(3)°, γ = 83.778(3)°, space group P $\bar 1$ , V = 612.42(7) ų, Z = 1, d _x = 1.264 g/cm³. The structure is molecular; the copper atom has a square plane coordination formed by the oxygen atoms of two β-diketonate ligands; the average Cu-O distance is 1.895 Å, ∠O-Cu-O 92.5°. Only van der Waals interactions are realized between the molecules in the structure. The temperature dependences of the saturated vapor pressure were studied by the mass transfer technique, and the standard thermodynamic parameters of sublimation were derived for the complex, ΔH _subl ⁰ = 115.6 ± 1.1 kJ/mol, ΔS _subl ⁰ = 204.9 ± 2.5 J/mol·K.     

Earth Alkaline Tetrathiosquarates. II. – Syntheses and Crystal Structures of SrC4S4·4 H2O and Ba4K2(C4S4)5·16 H2O

Concentrated aqueous solutions of strontium chloride and barium chloride, respectively, allow on addition of the potassium salt of tetrathiosquarate, K₂C₄S₄·H₂O, the isolation of the earth alkaline salts SrC₄S₄·4 H₂O ( 1 ) and Ba₄K₂(C₄S₄)₅·16 H₂O ( 2 ), both as dark red crystals. The crystal structure determinations ( 1 : orthorhombic, Pnma, a = 8.149(1), b = 12.907(2), c = 10.790(2) Å, Z = 4; 2 : orthorhombic, Pbca, a = 15.875(3), b = 21.325(5), c = 16.119(1) Å, Z = 4) show the presence of C₄S₄²⁻ ions with only slightly distorted D_4h symmetry having average C–C and C–S bond lengths of 1.41Å and 1.681Å for 1 and 1.450Å and 1.657Å for 2 . The structure of 1 contains concatenated edge‐sharing Sr(H₂O)₆S₂ polyhedra. The Sr²⁺ ions are in eight‐fold coordination with Sr–O distances of 2.50–2.72Å and Sr–S distances of 3.21Å, (C₄S₄)²⁻ acts as a chelating ligand towards Sr²⁺. The structure is closely related to the previously reported Ca²⁺ containing analogue, which is of lower symmetry belonging to the monoclinic crystal system. A supergroup‐subgroup relation between the space groups of both structures is present. The structure of 2 is made up of Ba²⁺ and K⁺ ions in eight and nine‐fold coordination by H₂O molecules and (C₄S₄)²⁻ ions which act as chelating ligands towards one cation and bridging between two cations. The coordination polyhedra of the cations are connected by common edges and corners in two dimensions to layers which are connected by tetrathiosquarate ions to a three‐dimensional network. The infrared and Raman spectra show bands typical for the molecular building units of the two compounds.     

Zur Kenntnis von Ba10Fe8Pt2Cl2O25

About Ba₁₀Fe₈Pt₂Cl₂O₂₅ The crystal structure of Ba₁₀Fe₈Pt₂Cl₂O₂₅ has been solved by direct methods, using intensity data collected by means of an automatic diffractometer (MoKα). It crystallizes in the hexagonal space group D–P6₃/mmc: a = 5.8034(4) Å, c = 24.997(5) Å, Z = 1. Fe³⁺ ions occur in both octahedral and tetrahedral coordination. Two types of Ba²⁺ ions are formed, with ten and twelve neighbouring atoms. The structure consists of plane connected FeO₆ and PtO₆ octahedra which are connected by corner shared FeO₄ tetrahedra.     

Crystal structure of EuLaCuS<Subscript>3</Subscript>

The crystal structure of the EuLaCuS₃complex sulfide synthesized for the first time has been solved by X-ray powder diffraction. Crystals are orthorhombic, space group Pnma, Ba₂MnS₃-type structure, a = 8.1297(3) Å, b = 4.0625(1) Å, c = 15.9810(4) Å, V = 527.80(3) ų, Z = 4, and ρ_calc = 5.669 g/cm³. The La and Eu atoms are randomly disordered over two crystallographic positions with a coordination number of 7, and the Eu(La)-S bond lengths range from 2.892(6) to 3.078(6) Å. The CuS₄ tetrahedra with Cu-S interatomic distances of 2.358(5)–2.40(1) Å form chains running along the b axis.     

Ba7Fe6F32 · 2H2O: Original isolated trimers [Fe3F16]7− in a new defective jarlite-type compound

Ba₇Fe₆F₃₂ · 2H₂O was prepared from HF aqueous solution in a teflon bomb (Berghof) at 180°C. A partial exchange F^?/OH^? can be realized in more diluted HF medium and leads to Ba₇Fe₆F_32–x(OH)_x · 2H₂O. The compounds crystallize in the monoclinic system, space group C2/m (Z = 2) with a = 17.023(1) Å, b = 11.482(1) Å, c = 7.624(1) Å, β = 101.13(1)° for x = 0 and a = 17.036(2) Å, b = 11.489(1) Å, c = 7.620(2) Å, β = 101.48(1)° for x ≈? 5.3. The structures were determined from 2 256 and 1 343 independent reflections for x = 0 and x ≈? 5.3 respectively, collected with a Siemens AED2 four-circle diffractometer with the MoKα radiation (R = 0.0235 and R_w = 0.0240 for x = 0 and R = 0.0324 and R_w = 0.0335 for x ≈? 5.3). The structure, closely related to that of the Jarlite-type, is built up from isolated octahedra trimers [Fe₃F₁₆]^7?, connected together by Ba²⁺-cations. The location of anions and water molecules is discussed from bond valence calculations. Magnetic and Mössbauer studies are reported and discussed.     

Die Neubestimmung der K2CuF4-Struktur

Redetermination of the K₂CuF₄ Structure The structure of K₂CuF₄ was redetermined by x-rays. An enlarged tetra-gonal unit cell of dimensions a = 5.858, c = 25.42 Å was found. The refinement in spacegroup D–I4c2 yielded R = 0.06. Contrary to former findings the JAHN-TELLER- distortion of the CuF₆-octahedra corresponds to a tetragonal elongation with distances Cu–F = 1.92 Å (4 ×) and 2.22 Å(2×).     

Diaquabromo(18-crown-6)rubidium and triaqua(18-crown-6)barium dibromide monohydrate: Synthesis and crystal structures

Two complexes are synthesized: diaquabromo(18-crown-6)rubidium [RbBr(18-crown-6)(H₂O)₂] (I) and triaqua(18-crown-6)barium dibromide monohydrate [Ba(18-crown-6)(H₂O)₃]²⁺ 2Br^? · H₂O (II). The orthorhombic structure of compound I (space group Pnma, a = 10.124 Å, b = 15.205 Å, c = 12.544 Å, Z = 4) and the monoclinic structure of compound II (space group C 2/c, a = 17.910 Å, b = 10.315 Å, c = 14.879 Å, β = 123.23°, Z = 4) are determined by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.063 (I) and 0.042 (II) for all 2293 (I) and 3363 (II) independent measured reflections (CAD-4 automated diffractometer, λMoK _α). The complex molecule [RbBr(18-crown-6)(H₂O)₂] in compound I and the randomly disordered cation [Ba(18-crown-6)(H₂O)₃]²⁺ in compound II are of the host-guest type: their Rb⁺ or Ba²⁺ cation (its coordination number is nine) is located in the cavity of the 18-crown-6 ligand and coordinated by all six O atoms. In structure I, the coordination polyhedron of Rb⁺ is a distorted hexagonal pyramid with a triple apex at the Br^? ligand and two O atoms of the water molecules. In structure II, the Ba²⁺ polyhedron is a distorted hexagonal bipyramid with one apex at the O atom of the water molecule and the other split apex at two O atoms of water molecules.     

Barium (nitrilotriacetato)oxalatocobaltate(III) trihydrate Ba[Co(Nta)(C<Subscript>2</Subscript>O<Subscript>4</Subscript>)] · 3H<Subscript>2</Subscript>O: Crystal structure

Crystals of Ba[Co(Nta)(C₂O₄)] · 3H₂O were prepared, and their structure was solved by X-ray diffraction (monoclinic space group P2₁/c), a = 10.0111(10) Å, b = 10.2838(6) Å, c = 14.2748(15) Å, ß = 100.350(12)°, Z = 4). The local environment of a Ba²⁺ ion includes two O atoms of water molecules and seven O atoms of the carboxyl groups of Nta^3? and C₂O ₄ ^2? ions of five complex anions. Honeycomb type layers can be distinguished in the crystal lattice; within the layers, each Ba²⁺ atom interacts with three complexes and vice versa. In addition, each Ba atom of the layer is bonded to complexes of the upper and lower layers. Thus, the crystal represents a three-dimensional coordination polymer.     

Une nouvelle famille structurale: Les oxydes Ln4−2xBa2+2xZn2−xO10−2x (Ln = La,Nd)

Two original compounds, Ln_4?2xBa_2+2xZn_2?xO_10?2x, were isolated for Ln = La, Nd and 0 ≤ x ≤ 0.25. These oxides are tetragonal with a and c parameters close to 6.91 and 11.59 Å, respectively, for lanthanum, and 6.75 and 11.54 Å for neodymium. The structure of these phases was determined from X-ray powder patterns in the most symmetric space group, $\text{I}\text{4}\text{mcm}$, using Patterson and Fourier functions for x = 0. The structure should be compared to that of copper oxides La_4?2xBa_2+2xCu_2?xO_10?2x: it is built up of identical Ln₂O₅ layers formed from face- and edge-sharing LnO₈ polyhedra, between which Ba²⁺ and Zn²⁺ ions are inserted. Contrary to the copper compounds, two successive Ln₂O₅ layers are rotated by 90°, involving a doubling of c. The result for Zn²⁺ is tetrahedral coordination, while the coordination of Ba²⁺ becomes a bicapped antiprism.