Über Gemischtvalente Sauerstoffperowskite vom Typ Ba3BIIIPtRuO9

Mixed-valent Perovskites of the Type Ba₃B^IIIPtRuO₉ Compounds of type Ba₃B^IIIPtRuO₉ – with a mean oxydation state of the noble metals of +4.5 – crystallize with B^III ? Gd? Lu, Y in a variant of hexagonal BaTiO₃ type with ordered cationic distribution. Intensity calculations on powder data of Ba₃YPtRuO₉ (a = 5.88₈; c = 14.7₀ Å) gave in the space group P6₃/mmc (sequence (hcc)₂) a refined, intensity related R′ value of 5.9%. With B^III ? Eu the lattice is monoclinic and for B^III ? Sm, Nd, La triclinic distorted.     

Über Perowskite der Zusammensetzung A2BUIVO6 mit A,B = Ba,Sr, Ca,Mg und Pb

On Perovskites of the Composition A₂BU^IVO₆ with A, B = Ba, Sr, Ca, Mg, and Pb The influence of the A und B ions on the charge transfer O → U are studied by diffuse reflectance measurements. They are completed by vibrational spectroscopic spectroscopic and structural investigations.     

Über Verbindungen des Typs Ba2BIIIOsVO6

Compounds of Type Ba₂B^IIIOs^VO₆ The black perovskites of type Ba₂B^IIIOs^VO₆ crystallize cubic (B^III ? Pr, Nd, Sm—Lu, Y) and rhombohedral (B^III ? La) respectively; the cell volumina decrease linearily with (r_BIII)³. Intensity calculations on powder data for Ba₂YOsO₆ (space group Fm3m—O) and Ba₂LaOsO₆ (space group R3m—D) gave the intensity related R′ values of 4.6% and 5.0% respectively. The results of the vibrational spectroscopic investigations are reported in common with the bond orders, M? O distances and mean amplitudes and compared with the corresponding values of the series Ba₂B^IIIIr^VO₆ and Ba₂B^IIIRu^VO₆.     

Über geordnete Perowskite mit Kationenfehlstellen. XI. Verbindungen vom Typ ABB□1/4WVIO6 ≙ ABIIB□WO24 mit AII,BII = Ba,Sr

On Ordered Perovskites with Cationic Vacancies. XI. Compounds of Type A B B □_1/4W^VIO₆ ? A B^IIB □W O₂₄ with A^II, B^II = Ba, Sr Depending on the ionic radii of the two and three valent cations in the perovskites of type ABB □_1/4W^VIO₆ ?; AB^IIB □WO₂₄ order disorder phenomena are present. The results of the x-ray and vibrational spectroscopic investigations as well as the diffuse reflectance spectra and the visible photoluminescence are reported.     

Über Neue Hexafluororhodate(IV): AIIRhIVF6 (AII = Ba,Sr, Ca,Mg, Zn,Cd, Hg,Ni sowie Cu)

On Novel Hexafluoro Rhodates(IV): A^IIRh^IVF₆. (A^II = Ba, Sr, Ca, Mg, Zn, Cd, Hg, Ni, Cu) We obtained hithertoo unknown BaRhF₆ and SrRhF₆ (both lemon yellow) of (hexag.) BaSiF₆?Type [a = 7.37₉, c = 7.21₁Å bzw. a = 7.15₇, c = 6.94₈ Å] as well as CaRhF₆ (light yellow) [a = 5.26₇, c = 14.61₂ Å], MgRhF₆ (light yellow) [a = 5.02₇, c 13.51₁Å], ZnRhF₅ (light yellow) [a = 4.99₆, c = 13.68₃ Å], CdRhF₆ (light yellow) [a = 5.,12₈ c = 14.44₇ Å], HgRhF₆ (orange) [a = 5.13₃, c = 14.67₆ Å], NiRhF₆ (light brown) [a = 4.96₀, c = 13.51₄ Å] all of (hexag.) LiSbF₆?type. The strukture of CuRhF₆ (light brown) is yet unknown.     

Über geordnete Perowskite mit Kationenfehlstellen. X. Verbindungen vom Typ ABB□1/4MVIO6 ≙ ABIIB□MO24 mit AII,BII = Ba,Sr, Ca und MVI = U,W

On Ordered Perovskites with Cationic Vacancies. X. Compounds of Type A B B □_1/4M^VIO₆ ? A B^IIB □M O₂₄ with A^II, B^II = Ba, Sr, Ca and M^VI = U, W Perovskites of type Ba₈B^IIB₂^III□UO₂₄ show polymorphic phase transformations of order disorder type. An 1:1 ordered orthorhombic HT form is transformed into a higher ordered LT modification with a fourfold cell content (four formula units Ba₈B^IIB□U₄O₂₄), compared to cubic 1:1 ordered perovskites A₂BMO₆. In the series Ba₈BaB□W₄O₂₄ and Sr₈SrB□W₄O₂₄ different ordering phenomena are observed. In comparison with 1:1 ordered cubic perovskites A₂BMO₆, the cell contains eight formula units AB^IIB□W₄O₂₄. The higher ordered cells with U^VI and W^VI are face centered, which has its origin in an ordering of cationic vacancies.     

Über Ruthenium-Perowskite vom Typ Ba2BRuO6 und Ba3BRu2O9 mit B = Indium,Rhodium

On Ruthenium perovskites of type Ba₂BRuO₆ and Ba₃BRu₂O₉ with B = Indium, Rhodium The black perovskites Ba₂InRu⁵⁺O₆ and Ba₃InRu₂O₉ (mean oxydation state of ruthenium: +4.5) adopt the hexagonal BaTiO₃ structure and form a continuous series of mixed crystals. According to the intensity calculations and analysis of the vibrational spectroscopic data an ordered distribution between indium and ruthenium is present: 1:1 order in Ba₂InRuO₆ (space group P3 m1 ? D; R′ = 5.3%); 1:2 order in Ba₃InRu₂O₉ (space group P6₃/mmc ? D; R′ = 4.6%). The corresponding black Rh compounds, Ba₂RhRuO₆ and Ba₃RhRu₂O₉, crystallize in the rhombohedral 9 L type of BaRuO₃.     

Über Perowskite Ba2BBTeVIO6

On Perovskites Ba₂B B Te^VIO₆ Compounds of composition Ba₂BBTe^VIO₆ with B^I = Li, Na; B^III = La, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Yb, Y, In, Sc crystallize in a cubic 1:1 ordered perovskite structure. The vibrational spectroscopic investigations show, that more species of TeO₆ octahedra are present in the lattice.     

Über gemischtvalente Ruthenium-Perowskite Ba3B3+Ru24,5+O9 – zur katalytischen Aktivität von Sauerstoffperowskiten mit vier- und fünfwertigen Edelmetallen

On Mixed Valent Perovskites Ba₃B³⁺Ru₂^4,5+O₉ – Catalytic Activity of Perovskite Oxides with Noble Metals The black compounds Ba₃B³⁺Ru₂O₉ crystallize with B³⁺ = La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Y in a hexagonal BaTiO₃ structure (6 L, sequence (hcc)₂) with an ordered distribution (1:2 order) of B³⁺ and ruthenium (BO₆ single octahedra; Ru₂O₉ double groups). The mean oxidation state of ruthenium is about +4.5. The properties are compared with that of other isotypic stacking polytypes Ba₃B³⁺M₂^4,5O₉ (M₂ = IrRu, Ir₂, PtRu) and Ba₃B²⁺M₂⁵⁺O₉ (M = Ru, Ir). The results of activity tests concerning the efficiency of perovskite oxides with noble metals in respect of the oxidation of CO or CH_x and the reduction of NO_x are reported.     

Über die Oxydation des O-Methylbulbocapnins mit Jod

The oxidation product obtained by treatment of bulbocapnine methyl ether ( 2a ) with iodine in ethanol/water is not the tetradehydroaporphinium salt 4 as assigned by Gadamer & Kuntze, but a dimer of structure 3 . Reduction of 3 with zinc in dilute sulfuric acid gives rac-bulbocapnine methyl ether, whereas reduction with complex hydrides affords the diastereomeric dimers 7a and 7b .     

Über Phosphorstickstoffverbindungen,XXXII. Über Vier- und fünfgliedrige Heterocyclen mit Phosphor,Stickstoff und Kohlenstoff im Ring

On reacting of oxamide with PCl₅ the syntheses of the new N-, C- and pentavalent phosphorus containing heterocycles I and II (see “Inhaltsübersicht”), built up from interconnected four- and fivemembered ring systems, have been achieved. Reaction of N, N′- dimethyloxamide with PCl₃ yields the compound III which may be chlorinated to IV. An intermolecular reaction between the PCl₃- and carbonyl groups of IV gives V. The fivemembered ring systems III and V may each be linked together via N? CH₃ bridges, i. e. via P? N(CH₃)? P and P(O)? N(CH₃)? P(O) units, respectively. N, N′- dimethyloxamide reacts with PCl₅ to form a mixture of fivemembered heterocycles containing trivalent phosphorus (as a PCl group) and chlorinated carbon.     

Über Perowskitphasen des Systems Ba2Y0,67U1−xWxO6

On Perovskite Phases of the System Ba₂Y_0,67U_1?xW_xO₆ A solid solution series is formed between the polymorphic perovskites Ba₂Y_0.67UO₆ and Ba₂Y_0.67WO₆ (cubic: a = 8.37₂ Å; hexagonal: a = 4× 5.88₁ Å and c = 4× 7.77₈ Å). The structure is cubic between x = 0.1 and 0.99 and for x > 0.95 hexagonal as well. Strong deviations from the ideal behaviour are detectabel with spectroscopic methods. The shape of the UO₆ and WO₆ octahedrons experiences only minor changes within the series.     

Über die Ordnung von BIII und MV in Perowskiten vom Typ ABIIIMVO6 (AII  Ba,Sr; MV  Sb,Nb, Ta)

On the Ordering of B^III and M^V in Perovskites of Type A B^IIIM^VO₆ (A^II ? Ba, Sr; M^V ? Sb, Nb, Ta) The perovskites Ba₂B^IIISbO₆ crystallize monoclinic (B^III ? La, Pr, Nd) and cubic (B^III ? Sm, Eu, Gd, Tb, Dy, Yb, Lu, Y) respectively. The Sr compounds, Sr₂B^IIISbO₆, have a monoclinic (B^III ? Nd, Sm, Eu, Dy), orthorhombic (B^III ? Yb, Lu, Y, Sc) or cubic (B^III ? In, Ga) perovskite structure. By intensity calculations and vibrational spectroscopic investigations deviations from a complete order between B^III and Sb^V are detectable. For perovskites Ba₂B^IIIM^VO₆ with M^V ? Nb, Ta the incompleteness of cationic order can be demonstrated as well.     

Über Verbindungen des Typs Ba3SE2TeO9

Compounds of the Type Ba₃RE₂TeO₉ In the BaO? RE₂O₃? TeO₃ system homogeneous perovskite compounds of formula Ba₃RE₂TeO₉ with RE = Nd, Sm–Gd, Dy–Lu, and Y are formed under special preparation conditions. With RE = ND and Sm A monoclinic lattice is observed whereas for the other RE a primitive cubic (a = 4.30₃ Å (Eu) to a = 4.21₄ Å (Lu)) lattice is found.     

Oxometallate neuen Typs: Über Ba3NaNbO6 und Ba3NaTaO6

Oxometallates of a new Type: On Ba₃NaNbO₆ and Ba₃NaTaO₆ For the first time in form of colourless, transparent single crystals of Ba₃NaNbO₆ [annealed mixtures of BaO, Na₂O and Nb₂O₅, Ba : Na : Nb = 3.3 : 1.1 : 1, Ni-cylinder, 1100°C, 3d] as well as Ba₃NaTaO₆ [annealed mixtures of BaO, Na₂O and Ta₂O₅, Ba : Na : Ta = 3.3 : 1.1 : 1, Ni-cylinder, 1100°C, 3d] have been prepared. The crystal structure was solved by fourcycle-diffractometer data [Ba₃NaNbO₆: Mo? Kα , 356 out 356 I₀ (hkl), space group R3 c with a = 1026.6(1)pm, c = 1195.3(2)pm (Guinier-Simon powder data), Z = 6, R = 2.4%, R_w = 2.0% and Ba₃NaTaO₆: Ag? Kα , 498 out of 498 I₀ (hkl), space group R3 c with a = 1027.6(1)pm, c = 1196.0(2)pm (Guinier-Simon powder data), Z = 6, R = 4.9%, R_w = 4.4%], parameters see text. The Ba₃M part of structure (M = Nb, Ta) corresponds to a slightly (hexagonal) deformed Nb₃Al arrangement with Na inserted along [001] between adjacent M^v, which are nearly perfectly octahedrally surrounded by 6 O. The structural relations are deduced by Schlegel Diagrams. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Ionic Radii, MEFIR, as well as Charge Distribution, CHARDI, are calculated.     

Über Verbindungen vom Typ Ba3BIIMO9 mit BII  Mg,Ca, Sr,Ba und MV  Nb,Ta

Compounds of the Type Ba₃B^IIM O₉ with B^II ? Mg, Ca, Sr, Ba, and M^V ? Nb, Ta The hexagonal perovskites Ba₃B^IIMO₉ (M^V ? Nb, Ta) crystallize with B^II ? Mg Ca in a 3 L structure (sequence (c)₃) and B^II ?; Sr in the hexagonal BaTiO₃ type (6 L; sequence (hcc)₂) with an 1:2 order for the B and M ions. Intensity calculations for Ba₃SrNb₂O₉ and Ba₃SrTa₂O₉ gave in the space group P6₃/mmc a refined, intensity related R′ value of 8.4% (Nb) and 9.0% (Ta) respectively. For B^II ? Ba the perovskite Ba₃BaTa₂O₉ has an orthorhombic distorted 6 L structure and forms with Ba₃SrTa₂O₉ a continuous series of mixed crystals (Ba₃Sr_1?xBa_xTa₂O₉). In the system Ba₃Sr_1?xBa_xNb₂O₉ the range of existence of the hexagonal BaTiO₃ type is confined to the Sr richer end. The pure Ba compound possesses a proper structure type (5 L: Ba₅BaNb₃□O_13.5□_1.5).     

Über Polyanion-Polykation-Komplexe mit Polyphosphat

Polyanion-Polycation Complexes with Polyphosphate With two Na polyphosphates of different molar weight and a series of cationic polyelectrolytes (polydimethyldiallylammonium chloride, polyethylenimine, cationically modified polyacryloamides of different charge density) polysalts (symplexes) have been prepared. The precipitates were investigated with regard to stoichiometry of cationic to anionic groups, with regard to swelling in water, and with regard to morphology. Applying special conditions of component concentration, stoichiometric 1:1 symplexes were obtained also with polyphosphate. According to our results, the cohesion in these polyphosphate symplexes is caused mainly by electrostatic forces only, in contrast to symplexes with anionic cellulose derivatives.     

Über Bleisilberphosphate mit Apatitstruktur

On Lead Silver Phosphates with the Apatite Structure The hitherto unknown leas silver phosphate (Pb₈Ag₂PO₄)₆ has been prepared. It has an apatite structure with unoccupied halide positions like the analogous lead alkali compounds and forms solid solutions with Pb₁₀(PO₄)₆O, Pb₁₀(PO₄)₆(OH)₂, and Pb₁₀(PO₄)₆Cl₂. At 800°C, Pb₈Ag₂(PO₄)₆ decomposes to solid Pb₃(PO₄)₂ and PbAgPO₄. (Pb, Ag) apatites have been precipitated from aqueous solutions. On the side being richer in Ag they can approximately be formulated as solid solutions between Pb₈Ag₂(PO₄)₆ and Pb₁₀(PO₄)₆(OH)₂. However, the i.r. spectrum reveals clear differences compared with thermal and hydrothermal preparations. The distribution of cations shows nonideal behaviour with reduced tendency for fixation of Ag⁺, if the content of Ag in the precipitate is high. The compound PbAgPO₄ decomposes below 520°C to Pb₈Ag₂(PO₄)₆ and Ag₃PO₄. The arsenate apatite Pb₈Ag₂(AsO₄)₆ decomposes below 530°C to Pb₃(AsO₄)₂ and Ag₃AsO₄.     

Über Reaktionen des P4S10 mit siliciumorganischen Verbindungen

Reactions of P₄S₁₀ with Organosilicon Compounds P₄S₁₀ ( 1 ) can be degraded with silicon-nitrogen compounds. 1 reacts with (CH₃)₃Si? N(CH₃)₂ ( 2 a ) and (CH₃)₃Si? N(C₂H₅)₂ ( 2 b ) to yield S?P[N(CH₃)₂]₂SSi(CH₃)₃ ( 3 a ) and ( 3 b ). By the reaction of 1 with [(CH₃)₃Si]₂S ( 4 ) S?P[S? Si(CH₃)₃]₃ ( 6 ) is formed in high yield. (C₆H₅PS₂)₂ ( 7 ) was used as a model to investigate the course of the reaction. This leads to C₆H₅P(S)? [N(CH₃)₂]SSi(CH₃)₃ ( 9 ) and C₆H₅P(S)[SSi(CH₃)₃]₂ ( 10 ). The reaction mechanism will be discussed. The n.m.r. data and mass spectra are reported.