Über ein neues Oxoiridat(IV): Ba7Ir6O19

Summary The so far unknown compound Ba₇Ir₆O₁₉ was prepared by long time solid state reactions using a flux of BaCl₂. X-ray single crystal work lead to the space group C _2h ³ —C2/m;a=14.913;b=5.778;c=10.979 Å; =99.58°;Z=2. It crystallizes with a new structure type characterized by three face-shared octahedra. The Ir₃O₁₂-groups build up a threedimensional network with an incorporated Ba/O-frame.

     

Ein neues Oxotantalat mit bronzeähnlicher Kristallstruktur: Ba4CoTa10O30

Solide state reactions lead to the hitherto unknown compound Ba₄CoTa₁₀O₃₀. X-ray single crystal work (space group C _2v ¹⁴ -Amm2,a=3.905,b=10.203 andc=14.954 Å) shows, that the octahedron network of Ba₄CoTa₁₀O₃₀ is conform to the Na₂Nb₁₂O₃₀ F₂-Type. On the other hand the occupation of the tunnels is related to the bronze-structure. The different structure types are discussed.

     

Ein neues Oxometallat mit Mangan(II): Ba5Mn4Nd8O21

On a New Oxometallate of Manganese (II): Ba₅Mn₄Nd₈O₂₁ Single crystals of Ba₅Mn₄Nd₈O₂₁ were prepared for the first time by CO₂-Laser technique using H₂-atmosphere. It was investigated by a single crystal X-ray diffractometer study. Ba₅Mn₄Nd₈O₂₁ crystallizes with tetragonal symmetry space group: C? I4/m; a = 14.2104 Å; c = 5.8581 Å; Z = 2. Mn²⁺ is found in square pyramids of oxygen.     

Die erste Verbindung mit Mn2+ der Stoffklasse BaMLn2O5: BaMnDy2O5

The First Compound of BaMLn₂O₅-Type Containing Mn²⁺: BaMnDy₂O₅ Single crystals of the hitherto unknown compound BaMnDy₂O₅ were prepared by CO₂-Laser technique and H₂ atmosphere. Four circle diffractometer measurements led to space group D¹⁶_2h-Pnma, a = 12.428; b = 5.766; c = 7.143 Å; Z = 4. It is isotypic to BaCuSm₂O₅ and shows Mn²⁺ in square pyramids of oxygen.     

Ein neues Chloropalladat(II): BaPdCl4

A New Chloropalladate(II): BaPdCl₄ BaPdCl₄ was prepared through reaction of barium chloride and palladium dichloride (molar ratio 2:1) with the aid of the Bridgman technique. According to a X‐ray single crystal investigation, BaPdCl₄ crystallizes with the orthorhombic crystal system (space group Pbcn (No. 60), Z = 4, a = 686.7(1), b = 1258.8(2) pm, c = 750.2(2), R_all = 0.0383). The crystal structure is built up from square planar [PdCl₄] units which are linked together by Ba²⁺ ions in an eightfold coordination.     

Ein neues Oxochromat: SrNi2Cr8O15 vom Strukturtyp BaV10O15

Summary A new quaternary oxochromate(III) was prepared by solid state reaction. Single crystal X-ray investigations of SrNi₂Cr₈O₁₅ show that this compound belongs to the BaV₁₀O₁₅ type. [Space group D _2h ¹⁸ - Ccmb,a=10.042;b=11.413;c=9.260 Å;Z=4.] Ni²⁺ and Cr³⁺ occupy the octahedrally coordinated point positions statistically. The surrounding of Sr²⁺ is similar to the iso- and heteropolyacids.

     

Ein neuer Strukturtyp mit flächenverknüpften BaO6-Oktaedern: Ba6Nd2Al4O15

Summary A compound Ba₆Nd₂Al₄O₁₅ with a new structure-type was prepared by solid state reaction. It crystallizes with hexagonal symmetry, space group C _6v ⁴ – P 6₃mc;a=11.5696;c=6.9662 Å;z=2. Ba₆Nd₂Al₄O₁₅ has a dominating Ba/O-framework with incorporated AlO₆-octahedra and AlO₄-tetrahedra. A main feature of the structure are face connected BaO₆-octahedra. One of the point positions of the heavy atoms is occupied statistically by Ba²⁺ and Nd³⁺.

     

Ein neues Mangan(II)-Oxowolframat: Mn3WO6

On a New Manganese(II) Oxotungstate: Mn₃WO₆ Single crystals of Mn₃WO₆ were prepared by CO₂-LASER technique in H₂-atmosphere and investigated by single crystal X-ray work. It crystallizes with rhombohedral symmetry, space group C? R3 with the hexagonal lattice constants a = 8.8931 Å; c = 10.4782 Å and Z = 6. Mn₃WO₆ is isotypic to Mg₃TeO₆ and α-Ca₃UO₆ and characterized by to each other isolated WO₆ octahedra. The surrounding of them by six inner-sphere and six outer-sphere MnO₆ polyhedra is discussed.     

Ein neues metastabiles Zinkoxovanadat: Zn4V2O9

For the first time Zn₄V₂O₉ was prepared and investigated by single crystal X-ray methods. The metastable compound exists between a CO₂-Laser generated flux and the solid ZnO/V₂O₅ material. The quenched light brown crystals show a monoclinic symmetry (space group C ₂ ² —P2₁,a=10.488 (5),b=8.198 (6),c=9.682 (5) Å; =118.66 (4)°;Z=4]. Zn₄V₂O₉ has a characteristic Zn/O-framework with incorporated V⁵⁺ in tetrahedral coordination. The relationship to Zn₄Ta₂O₉ and the calculation of the madelung part of lattice energy (MAPLE) in respect to the metastable character are discussed.

     

Synthesis and Characterization of the Synthetic Minerals Villyaellenite and Sarkinite,Mn5(AsO4)2(HAsO4)2 · 4H2O and Mn2(AsO4)(OH)

Using hydrothermal methods, two manganese arsenates have been synthesized and characterized by single crystal X‐ray diffraction. The products Mn₅(AsO₄)₂(HAsO₄)₂ ?4H₂O ( 1 ) and Mn₂AsO₄(OH) ( 2 ), the Mn end‐members of the minerals villyaellenite and sarkinite, respectively, have been obtained (crystal data 1 : monoclinic, C2/c, a = 18.109(4), b = 9.332(2), c = 9.809(2) Å, β = 96.172(4)?, Z = 4; 2 : monoclinic, P2₁/c, a = 10.219(2), b = 13.613(2), c = 12.780(2) Å, β = 108.834(2)?, Z = 16). In both compounds a three‐dimensional framework of edge‐sharing MnO polyhedra is observed. Based on the availability of the all Mn2containing form of villyaellenite ( 1 ), the ordering scheme of the impurity cations of the natural samples could be confirmed. Magnetic susceptibility measurements of 1 indicate the presence of high‐spin Mn²⁺ ions. The comparison of the data on sarkinite ( 2 ) with the data obtained from the natural sample indicates that the mineral has either a very high Mn content, or an absence of impurity cation ordering.     

Ein Halogenooxoruthenat (IV,V): Ba6Ru2, 5Mn0, 5O12Cl2 mit neuem Strukturtyp

About a Halogenooxoruthenat (IV, V): Ba₆Ru_2,5Mn_0,5O₁₂Cl₂ with a New Structure Type Ba₆Ru_2.5Mn_0.5O₁₂Cl₂ was prepared and investigated by single crystal X-ray work (space group D—P3 m1; a = b = 5.799; c = 14.853 Å; Z = 1). This structure type is characterized by «isolated», face-sharing (Ru/Mn)₃O₁₂-octahedratriple. Calculations of the Coulomb term of lattice energy support the charge distribution (5⁺/4⁺/5⁺) within the groups (Ru/Ru_0.5Mn_0.5/Ru)₃O₁₂^10?. The coordination of barium by oxygen and chlorine within three different polyhedra is discussed in detail.     

Struktur‐ und magnetochemische Untersuchungen an den ternären Phosphaten Ba2MII(PO4)2 (MII = Mn,Co) und Strukturverfeinerung von BaNi2(PO4)2

Structural and Magnetochemical Studies at the Ternary Phosphates Ba₂M^II(PO₄)₂ (M^II = Mn, Co) and Refinement of the Crystal Structure of BaNi₂(PO₄)₂ Single crystals of the following phosphates were grown by the floating zone technique using a mirror furnace and their crystal structures refined (0,02 < R₁ < 0,04 and 0,04 < wR₂ < 0,10, resp.): Ba₂Mn(PO₄)₂ (a = 531.1(1), b = 896.8(1), c = 1625.6(3) pm, β = 90.26(1)°), Ba₂Co(PO₄)₂ (a = 529.8(1), b = 884.4(1), c = 1614.4(3) pm, β = 90.68(2)°) and BaNi₂(PO₄)₂ (a = 480.0(1), c = 2327.3(5) pm, Z = 3, space group R3). Both compounds Ba₂M^II(PO₄)₂ crystallize with Z = 4 in space group P2₁/n of the monoclinic Ba₂Ni(PO₄)₂ type; BaNi₂(PO₄)₂ has the hexagonal‐rhombohedral structure of the BaNi₂(AsO₄)₂ type. Magnetic measurements of powders of Ba₂Mn(PO₄)₂ and Ba₂Co(PO₄)₂ yielded room temperature moments of μ_eff = 5,73 and 4,93 μ_B, resp., but only the manganese compound obeys the Curie‐Weiss law down to low temperatures. Weak antiferromagnetic interactions at both compounds only near T_M ≈ 5 K lead to a reciprocal susceptibility minimum.     

RbFe[BP2O8(OH)]: Ein neues Borophosphat mit offen-verzweigten Vierer-Einfach-Tetraederketten

RbFe[BP₂O₈(OH)]: A New Borophosphate Containing Open-Branched Tetrahedral Vierer-Einfach Chains RbFe[BP₂O₈(OH)] is formed under mild hydrothermal conditions (T = 165–170 °C) from a mixture of RbOH_(aq), FeCl₂ · 4 H₂O, H₃BO₃ and H₃PO₄. The crystal structure of the monoclinic compound was solved by x-ray single crystal methods (space group P2₁/c, No. 14): a = 935.8(5) pm, b = 833.9(6) pm, c = 965.6(5) pm; β = 101.69(4)°; Z = 4. The anionic partial structure contains open-branched vierer-einfach chains [BP₂O₈(OH)]^4–, which are formed by alternating borate and phosphate tetrahedra sharing common corners. Fe³⁺ is in an octahedral coordination (FeO₅(OH)), while Rb⁺ is irregularly coordinated by ten oxygen-functions of neighbouring tetrahedra.     

Crystal Structure Determination of Tetrabarium‐digalliumoxide,Ba4Ga2O7

Single crystals of a new barium oxogallate were obtained by growth from a melt at 1500 °C. The compound is monoclinic, with cell parameters a = 17.7447(10) Å, b = 10.6719(5) Å, c = 7.2828(5) Å, β = 98.962(7)°, V = 1362.3(2) ų. The diffraction pattern shows systematic absences corresponding to the space group P12₁/c1. The structure was solved by direct methods followed by Fourier syntheses, and refined using a single crystal diffraction data set (R1 = 0.032 for 2173 reflections with I > 2σ(I)). The chemical composition derived from structure solution is Ba₄Ga₂O₇, with a unit cell content of Z = 6. Main building units of the structure are GaO₄ tetrahedra sharing one oxygen atom to form Ga₂O₇ groups. The Ga–O–Ga bridging angle of one of the two symmetrically independent groups is linear by symmetry. The dimers are crosslinked by barium cations coordinated by six to eight oxygen ligands.     

Zur Kenntnis eines Oxoargentato(I)-aurats(III): Ba4AgAuO6

On the Oxoargentato(I)-aurat(III): Ba₄AgAuO₆ The hitherto unknown compound Ba₄AgAuO₆ was prepared by oxidizing Ba/Au/Ag alloy with BaO₂/Ba(OH)₂ mixture in closed Ag tubes. X-ray single crystal investigation led to orthorhombic symmetry space group D-Cmcm; a = 13.275; b = 5.782; c = 11.396 Å; Z = 4. Ba₄AgAuO₆ shows distorted pentagonal bipyramidal polyhedra around Ba²⁺ and square planar AuO₄ polygones. Ag⁺ shows an unusual 2 + 2 coordination by O^2?.     

Einbau von Al3+ in Ir3O12-Oktaedertripel in Ba4Ir2AlO10

Incorporation of Al³⁺ in Ir₃O₁₂ Octahedra-Triple in Ba₄Ir₂AlO₁₀ Single crystals of Ba₄Ir₂AlO₁₀ were prepared by solid state/flux reactions. It crystallizes with orthorhombic symmetry: space group D–Cmca; a = 5.778; b = 13.352; c = 13.084 Å; Z = 4. The structure is characterized by face connection of three IrO₆- or Ir/AlO₆-octahedra. X-ray investigations show an ordered occupation of the centric octahedron by Ir and a statistically distribution of Ir and Al in the adjacent octahedra. Calculations of the coulomb term of the lattice energy support a charge distribution in the manner Ir⁵⁺/Al³⁺? Ir⁴⁺? Ir⁵⁺/Al³⁺.     

Cu4O12-Baugruppen aus planaren CuO4-Polygonen im Barium-Vanadyl-Oxocuprat(II)-phosphat Ba(VO)Cu4(PO4)4

Cu₄O₁₂ Groups Built of Square Planar CuO₄ Polygones in the Barium Vanadyl Oxocuprate(II) Phosphate Ba(VO)Cu₄(PO₄)₄ Single crystals of Ba(VO)Cu₄(PO₄)₄ have been prepared by solid state reactions just below the melting points of the reaction mixtures of BaP₂O₆, Cu₃(PO₄)₂, CuO, V₂O₅ and V₂O₃ in evacuated closed quartz glas tubes. The compound crystallizes with tetragonal symmetry, Space group D? P42₁2, a = 9.560(2), c = 7.160(2) Å, Z = 2. Special and new features of the crystal structure are to each other isolated Cu₄O₁₂ and (VO)(PO₄)₄ groups. The crystal chemistry of the Cu₄O₁₂ groups is discussed with respect to other compounds containing out of plane connected square planar MO₄ polygones.     

Darstellung und Kristallstruktur von Na2Sn2Se5 Ein neues Chalkogenostannat(IV) mit schichtförmigen Komplexanionen

Preparation and Crystal Structure of Na₂Sn₂Se₅ A Novel Chalcogenostannate(IV) with Layered Complex Anions Na₂Sn₂Se₅ was obtained from a stoichiometric mixture of Na₂Se, Sn, and Se powders through a solid state reaction at 450 °C. It crystallizes orthorhombic, space group Pbca with a = 13.952(6) Å, b = 12.602(2) Å, c = 11.524(2) Å; Z = 8 and undergoes peritectic decomposition at 471(2) °C. The crystal structure was determined at ambient temperature from diffractometer data (MoKα‐radiation) and refined to a conventional R of 0.040 (1490 F_o's, 83 variables). Na₂Sn₂Se₅ is characterized by layered complex anions running parallel to (100) which are built up by SnSe₄ tetrahedra sharing common corners. The mean Sn–Se bond length calculates as 2.252(2) Å. The Na⁺ cations are coordinated to 6 or 7 Se in irregular configurations. The crystal structure can be described as a stacking of distorted c. p. 3⁶ chalcogen layers and mixed square 4⁴ alkali‐chalcogen layers.     

Structural Characterization of Mn2+—ß″—Al2O3(Mn0.77Al10.46Mg0.54O17)

The structure of completely exchanged Mn²⁺—ß″—Al₂O₃(Mn_0.77Al_10.46Mg_0.54O₁₇) crystals has been investigated by single—crystal X—ray diffraction methods at room temperature (trigonal, R3¯, Z = 3, a = 560.65(7), c = 3329.3(9) pm). The manganese ions (Mn²⁺) are found to occupy Beevers‐Ross (56 %) and mid—oxygen positions (44 %) in nearly the same amounts. The crystal composition was confirmed by electron probe microanalyses on various crystals.     

Ein Fluoridphosphat von Mangan(III) mit ungewöhnlicher Schichtstruktur: Na7[Mn5F13(PO4)3(H2O)3]

A Fluoride Phosphate of Manganese(III) with Unusual Layer Structure: Na₇[Mn₅F₁₃(PO₄)₃(H₂O)₃] The title compound was crystallized from a solution of MnF₃ · 3 H₂O in aqueous HF by addition of NaH₂PO₄ · H₂O in 2 M phosphoric acid. The crystal structure has been determined at 295 and 150 K on a trigonal crystal twinned by merohedry: Space group P3c1, Z = 4, a = 1055,0(1), c = 2314,0(1) pm (a = 1052,5(1), c = 2304,2(1) pm at 150 K), wR₂ = 0.0651 (0.0651). The structure contains anionic layers formed by triangular moieties of three [MnF₃O₂(H₂O)] octahedra sharing one common μ₃-F atom and bridged by three phosphate groups. Three of those groups, respectively, are interconnected by two [MnF₃O₃] octahedra over six phosphate O-atoms to form a trigonal layer in the a,b plane. Stacking of these layers gives channels along the c axis in which most of the Na⁺ ions are located. The [MnF₃O₂(H₂O)] octahedra show strong elongation along the μ₃-F–Mn–OH₂ axis mainly due to the Jahn-Teller effect whereas in the [MnF₃O₃] octahedra with C₃ symmetry weak signs only of a dynamical Jahn-Teller-effect can be observed. The magnetic properties (μ_eff = 4.61 μ_B, 3-D ordering point T_N = 3.3 K) were determined on powders and possible magnetic exchange pathways are discussed.