Beiträge zur Chemie von Phosphorverbindungen mit Adamantanstruktur. XI. Über Darstellung und Eigenschaften von Phosphoroxidsulfiden der allgemeinen Formel P4O10−nSn (n = 2−9)

Contributions to the Chemistry of Phosphorus Compounds with Adamantane-like Structure. XI. Preparation and Properties of Phosphorus Oxide Sulfides of the General Formula P₄S_10?n S_n (n = 2?9) The reaction of P₄O₁₀ with P₄S₁₀ yields a mixture of phosphorus oxide sulfides of the general formula P₄O_10?nS_n. Depending on the molar ratio P₄O₁₀: P₄S₁₀ in the starting product different amounts of the individual phosphorus oxide sulfides occuring in this reorganization product are formed. Besides the well-known P₄O₆S₄ the compounds P₄O₇S₃, P₄O₅S₅, P₄O₄S₆, P₄O₃S₇, P₄O₂S₈, and P₄OS₉ occuring for the first time were obtained by fractional distillation or crystallization. The compound P₄O₈S₂ was identified by N.M.R. spectroscopy.     

Zur Kenntnis der Dialkalimetalldichalkogenide β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 und Rb2Te2

On Dialkali Metal Dichalcogenides β-Na₂S₂, K₂S₂, α-Rb₂S₂, β-Rb₂S₂, K₂Se₂, Rb₂Se₂, α-K₂Te₂, β-K₂Te₂ and Rb₂Te₂ The first presentation of pure samples of α- and β-Rb₂S₂, α- and β-K₂Te₂, and Rb₂Te₂ is described. Using single crystals of K₂S₂ and K₂Se₂, received by ammonothermal synthesis, the structure of the Na₂O₂ type and by using single crystals of β-Na₂S₂ and β-K₂Te₂ the Li₂O₂ type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na₂O₂ type to the Li₂O₂ type will be explained by means of the examples α-/β-Na₂S₂ and α-/β-K₂Te₂. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb₂S₂ is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.     

Acetylenic derivatives of metal carbonyls of the triad Fe,Ru, Os—XI Mass spectra of some binuclear complexes

The mass spectra of the following acetylenic derivatives of iron, ruthenium and osmium carbonyls are reported: the iron compounds Fe₂(CO)₆[C₂(C₆H₅)s₂]₂, Fe₂(CO)₆[C₂(CH₃)₂]₂ and Fe₂(CO)₆[C₂(C₂H₅)₂]₂, the ruthenium compounds Ru₂(CO)₆[C₂(C₆H₅)₂]₂, and Ru₂(CO)₆[C₂(CH₃)₂]₂ and the osmium compounds Os₂(CO)₆[C₂(C₆H₅)₂]₂, Os₂(CO)₆[C₂HC₆H₅]₂ and Os₂(CO)₆[C₂(CH₃)₂]₂. Iron compounds exhibit breakdown schemes where binuclear, mononuclear and hydrocarbon ions are present. On the other hand, ruthenium and osmium compounds fragment in a similar way and give rise to singly and doubly charged binuclear ions. Phenylic derivatives of ruthenium and osmium also give weak triply charged ions. The results are discussed in terms of relative strengths of the metal-metal and metal-carbon bonds.     

Beiträge zum chemischen Transport oxidischer Metallverbindungen. V. Der Transport ternärer und quaternärer Mischferrite über ihre Metallchloride

Contributions to the Chemical Transport of Metal Oxides. V. Transport of Ternary and Quaternary Mixed Ferrites by their Chlorides The transport by means of HCl as transporting gas in a closed system in the case of the ternary mixed ferrites (Ni_0,8Fe_2,2O₄, Mn_0,75Fe_2,25O₄, Mn_1,286Fe_1,714O₄) and the quaternary mixed ferrites (Mg_0,5Mn_0,5Fe₂O₄, Mg_0,75Mn_0,536Fe_1,714O₄, Mg_0,281Mn_0,469Fe_2,25O₄, Mn_0,5Zn_0,5Fe₂O₄, Mn_0,5Zn_0,45Fe_2,05O₄, Ni_0,5Zn_0,5Fe₂O₄) between T₂ = 1100?1000°C and T₁ = 1000?800°C was investigated. Transported crystals were characterized by chemical analysis and the saturation magnetization, the transport rate has been checked. In the case of Mn_0,5Zn_0,45Fe_2,05O₄ two phases were transported. By discussing the phase diagram an explanation is given.     

Equilibrium phase behavior of aqueous two-phase systems containing 17R4/L64 and citrates

The cloud points (CPs) of the copolymers 17R4 and L64 were first measured, and then the effects of salts ((NH₄)₃C₆H₅O₇, K₃C₆H₅O₇) on 17R4 and L64 were researched. After finishing the work described above, the temperature (278.15, 283.15, and 288.15) K of aqueous two-phase systems was determined, which consist of 17R4-(NH₄)₃C₆H₅O₇, 17R4-K₃C₆H₅O₇, L64-(NH₄)₃C₆H₅O₇, and L64-K₃C₆H₅O₇. Finally, the liquid–liquid equilibrium (LLE) data of binodal curve and the tie line for 17R4-(NH₄)₃C₆H₅O₇ aqueous two- phase systems (ATPSs) 17R4-K₃C₆H₅O₇ ATPSs, L64-(NH₄)₃C₆H₅O₇ ATPSs, and L64-K₃C₆H₅O₇ ATPSs were obtained. Nonlinear fitting of the empirical equation was used for making the diagram. The results showed that the change in the size of the two-phase areas increases with the increase of temperature. The capacity of the salts to induce phase segregation follows the Hofmeister series, that is, K₃C₆H₅O₇?>?(NH₄)₃C₆H₅O₇. In addition, the findings also showed that the phase separation ability of 17R4 is better than that of L64.     

Kryometrische Untersuchungen. IV. Lösungen von oxidischen Mo6+- und Cr6+-Verbindungen in geschmolzenem K2Cr2O7 und KNO3

The depression of freezing point of molten K₂Cr₂O₇ and KNO₃ as solvents was measured after addition of small concentrations of the following compounds: to K₂Cr₂O₇: MoO₃, CrO₃, (NH₄)₂CrO₄, K₂MoO₄, Na₂MoO₄, Li₂MoO₄, and Na₂Mo₂O₇, respectively; to KNO₃: CrO₃, (NH₄)₂Cr₂O₇ K₂Cr₂O₇, K₂CrO₄ and MoO₃, (NH₄)₆(Mo₇O₂₄) · 4 H₂O, K₂Mo₂O₇, K₂MoO₄, Na₂MoO₄ and Li₂MoO₄, respectively. It could be concluded from the measured values of the freezing point depression if a reaction between solvent and solute took place.     

Reactivity in the solid state between CoWO4 and RE2WO6 where RE = Sm, Eu, Gd

Reactivity in the solid state between CoWO₄ and some rare-earth metal tungstates RE₂WO₆ (RE = Sm, Eu, Gd) was investigated by the XRD method. Two families of new isostructural cobalt and rare-earth metal tungstates, Co₂RE₂W₃O₁₄ and CoRE₄W₃O₁₆, were synthesized. The Co₂RE₂W₃O₁₄ phases are formed by heating in air the CoWO₄ and RE₂WO₆ compounds mixed at the molar ratio 2:1, while the CoRE₄W₃O₁₆ phases are synthesized at the molar ratio of CoWO₄/RE₂WO₆ equals to 1:2. The Co₂RE₂W₃O₁₄ phases as well as the CoRE₄W₃O₁₆ compounds crystallize in the orthorhombic system. The Co₂RE₂W₃O₁₄ and CoRE₄W₃O₁₆ compound melt above 1150 °C. A melting manner of the Co₂RE₂W₃O₁₄ and CoRE₄W₃O₁₆ compounds was determined in an inert atmosphere. The formation of CoWO_4−x phase was observed during heating in an inert atmosphere.     

Nanostructuring in the process of the formation of mixed-anion compounds: Rare-earth borogermanates, germanophosphates, and borotungstates

Specific features of the textures (the preferred orientation of the nanometer building blocks) in the structures of mixed-anion compounds—rare-earth borogermanates, germanophosphates, and borotungstates that arise from the acid-base interaction in the Ln₂O₃-B₂O₃-GeO₂, Ln₂O₃-GeO₂-P₂O₅, and Ln₂O₃-B₂O₃-WO₃ systems (Ln = La-Gd)—have been studied. Based on characteristic texture traits, the mixed-anion compounds of early rare-earth elements can be divided into three groups: (i) Ln₂O₃: E_xO_y > 1, (ii) Ln₂O₃: E_xO_y = 1, and (iii) Ln₂O₃: E_xO_y < 1. Because of the dominant structural effect of the basic oxide Ln₂O₃ in the compounds of the first group, the structures of Nd₁₄O₈(BO₃)₆(GeO₄)₂ and Pr₁₁O₁₀(GeO₄)(PO₄)₃ are composed of infinite [LnO_n] bands and layers and discrete groups [EO_m] located in the interband and interlayer spaces. The dominant structural effect of the acid oxides [E_xO_y] in the compounds of the third group leads to the appearance of ring textures composed of [LnO_n], as well as to the appearance of chains and networks composed of [EO_m], in the structures of Ln(BGeO₅) and Ln(BO₂)(WO₄). Original Russian Text ￠ G.A. Bandurkin, N.N. Chudinova, G.V. Lysanova, K.K. Palkina, E.V. Murashcva, V.A. Krut’ko, G.M. Balagina, 2006, published in Zhurnal Neorganicheskoi Khimii, 2006, Vol. 51, No. 2, pp. 334–347.     

Synthesis of Inorganic Structural Isomers By Diffusion‐Constrained Self‐Assembly of Designed Precursors: A Novel Type of Isomerism

The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe₂: [(PbSe)_1.14]₄[NbSe₂]₄, [(PbSe)_1.14]₃[NbSe₂]₃[(PbSe)_1.14]₁[NbSe₂]₁, [(PbSe)_1.14]₃[NbSe₂]₂[(PbSe)_1.14]₁[NbSe₂]₂, [(PbSe)_1.14]₂[NbSe₂]₃[(PbSe)_1.14]₂[NbSe₂]₁, [(PbSe)_1.14]₂[NbSe₂]₂[(PbSe)_1.14]₁[NbSe₂]₁[(PbSe)_1.14]₁[NbSe₂]₁, [(PbSe)_1.14]₂[NbSe₂]₁[(PbSe)_1.14]₁[NbSe₂]₂[(PbSe)_1.14]₁[NbSe₂]₁. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance.     

The synthesis and structure of triphenylsiloxycyclotriphosphazenes

The triphenylsiloxy-substituted cyclotriphosphazenes, N₃P₃Cl₅OSiPh₃, gem-N₃P₃Cl₄(OSiPh₃)₂, N₃P₃(OSiPh₃)₆, and N₃P₃(OPh)₅OSiPh₃, have been prepared. The synthesis of gem-N₃P₃Cl₄(OSiPh₃)₂ involves the reaction of (NPCl₂)₃ with Ph₃SiONa to form the intermediates gem-N₃P₃Cl₄(OSiPh₃)₂(ONa) and gem-N₃P₃Cl₄(ONa)₂, which yield gem-N₃P₃Cl₄(OSiPh₃)₂ when treated with Ph₃SiCl. The compounds N₃P₃Cl₅OSiPh₃ and N₃P₃(OSiPh₃)₀ are formed by the condensation reactions of N₃P₃Cl₅OBuⁿ and N₃P₃(OBuⁿ)₆, respectively, with Ph₃SiCl. The compound N₃P₃(OPh)₅OSiPh₃ is synthesized by the reaction between N₃P₃(OPh)₅Cl and Et₃SiONa to first give the intermediate N₃P₃(OPh)₅ONa, which yields N₃P₃(OPh)₅OSiPh₃ when reacted with Ph₃SiCl. The structural characterization and properties of these compounds are discussed. The crystal and molecular structure of gem-N₃P₃Cl₄(OSiPh₃)₂ has been investigated by single-crystal X-ray diffraction techniques. The crystals are monoclinic with the space group P2₁/c with a = 16.850(8), b = 12.829(4), c = 18.505(15) Å, and β = 101.00(6)° with V = 3927 ų and Z = 4. © 1996 John Wiley & Sons, Inc.     

Piperazine Functionalization of C70 for Incorporation into Supramolecular Assemblies

The photochemical reaction of piperazine with C₇₀ produces a mono‐adduct (N(CH₂CH₂)₂NC₇₀) in high yield (67 %) along with three bis‐adducts. These piperazine adducts can combine with various Lewis acids to form crystalline supramolecular aggregates suitable for X‐ray diffraction. The structure of the mono‐adduct was determined from examination of the adduct I₂N(CH₂CH₂)₂NI₂C₇₀ that was formed by reaction of N(CH₂CH₂)₂NC₇₀ with I₂. Crystals of polymeric {Rh₂(O₂CCF₃)₄N(CH₂CH₂)₂NC₇₀}_n?nC₆H₆ that formed from reaction of the mono‐adduct with Rh₂(O₂CCF₃)₄ contain a sinusoidal strand of alternating molecules of N(CH₂CH₂)₂NC₇₀ and Rh₂(O₂CCF₃)₄ connected through Rh?N bonds. Silver nitrate reacts with N(CH₂CH₂)₂NC₇₀ to form black crystals of {(Ag(NO₃))₄(N(CH₂CH₂)₂NC₇₀)₄}_n?7nCH₂Cl₂ that contain parallel, nearly linear chains of alternating (N(CH₂CH₂)₂NC₇₀ molecules and silver ions. Four of these {Ag(NO₃)N(CH₂CH₂)₂NC₇₀}_n chains adopt a structure that resembles a columnar micelle with the ionic silver nitrate portion in the center and the nearly non‐polar C₇₀ cages encircling that core. Of the three bis‐adducts, one was definitively identified through crystallization in the presence of I₂ as ¹²{N(CH₂CH₂)₂N}₂C₇₀ with addends on opposite poles of the C₇₀ cage and a structure with C_2v symmetry. In ¹²{I₂N(CH₂CH₂)₂N}₂C₇₀, individual ¹²{I₂N(CH₂CH₂)₂N}₂C₇₀ units are further connected by secondary I2???N2 interactions to form chains that occur in layers within the crystal. Halogen bond formation between a Lewis base such as a tertiary amine and I₂ is suggested as a method to produce ordered crystals with complex supramolecular structures from substances that are otherwise difficult to crystallize.     

The systems Zr(Nb,Ti)(R)O2−δ, R=Yb, Ca—optimization of mixed conductivity and comparison with results of other systems (R=Y and Gd)

In this work we address the optimization of mixed conductivity in fluorite compounds based on zirconia. Phase relations of the new systems YbO_1.5-NbO_2.5-ZrO₂, and CaO-NbO_2.5-ZrO₂ are presented. The limit of the cubic defect fluorite phase in YbO_1.5-NbO_2.5-ZrO₂ closely resembles that of the system YO_1.5-NbO_2.5-ZrO₂, whilst in CaO-NbO_2.5-ZrO₂ is narrow extending to include composition Ca_0.255Nb_0.15Zr_0.595O_1.82 at 1500°C. The influence of dopant ion size, charge and composition on ionic conduction is assessed and parallels are drawn with the systems YO_1.5-NbO_2.5-ZrO₂ and YO_1.5-TiO₂-ZrO₂. Comparison of these results with published data on the Ti containing systems CaO-TiO₂-ZrO₂, GdO_1.5-TiO₂-ZrO₂ shows that the highest mixed conducting compositions can only be offered in the system YO_1.5-TiO₂-ZrO₂ out of all the systems here studied.     

Abläufe der Ammonolysen der Ammoniumhexafluorometallate des Aluminiums,Galliums und Indiums, (NH4)3MF6 (M = Al,Ga, In)

The Courses of the Ammonolyses of the Ammonium Hexafluorometalates of Aluminum, Gallium, and Indium, (NH₄)₃MF₆ (M = Al, Ga, In) The courses of the ammonolysis reactions of the ammonium hexafluorometalates (NH₄)₃MF₆ (M = Al, Ga, In) were investigated with the aid of in‐situ powder diffractometry and differential thermal analysis. Under these conditions, the reaction of (NH₄)₃AlF₆ with gaseous ammonia yields at about 360 °C AlF₃ via the intermediates NH₄AlF₄, Al(NH₃)₂F₃ and Al(NH₃)F₃. The ammonolysis of (NH₄)₃GaF₆ produces GaN at about 400 °C. Depending upon the actual reaction conditions, the intermediates NH₄GaF₄ and Ga(NH₃)F₃ as well as their ammonia adducts NH₄GaF₄ · NH₃ and Ga(NH₃)₂F₃ and the amide‐ammoniate Ga(NH₃)(NH₂)F₂ are observed. In the case of (NH₄)₃InF₆ the intermediates (NH₄)₃InF₆ · NH₃ and In(NH₃)F₃ may exist; there are also indications for the reduction of In(III) to In(I) and for the existence of In(NH₃)₂F and InF as products of the ammonolysis of (NH₄)₃InF₆.     

Alternativ-Liganden. III. Koordinatives verhalten von chelatliganden des typs me2XSi(Me2)CH2XMe2 (X  N und/oder P: Me  CH3)

Co-ordinative Properties of Chelating Ligands of the Type Me₂XSi(Me₂)CH₂XMe₂ (X ? N and/or P; Me ? CH₃) The reactions of the ligands L ? Me₂XSi(Me₂)CH₂XMe₂ (X ? N and/or P; Me ? CH₃) with M(CO)₆ and M(CO)₄norbor (norbor ? norbornadiene) (M ? Cr, Mo), respectively, yield derivatives of the types M(CO)₅L, M(CO)₄L, and M(CO)₄L₂, respectively. M(CO)₅L compounds are formed from the hexacarbonyls with Me₂NSiMe₂CH₂PMe₂, whereas the ligand Me₂NSiMe₂CH₂NMe₂ does not afford analogous derivatives under the same conditions. Even on substitution of the diene-ligand in M(CO)₄norbor by Me₂NSiMe₂CH₂PMe₂ the chelate complexes M(CO)₄NMe₂SiMe₂CH₂PMe₂ are not obtained, but the cis-disubstituted products M(CO)₄[PMe₂CH₂SiMe₂NMe₂]₂ with phosphorus acting as donor atom are produced. The ligands Me₂PSiMe₂CH₂XMe₂(X ? N, P) give the chelate complexes M(CO)₄PMe₂SiMe₂CH₂XMe₂ in high yields. The new compounds were identified by analytical and spectroscopic (PMR, IR, mass spectra) methods.     

La2O3 promotional effect to Co3O4/γ-Al2O3 catalyst in the oxidative dehydrogenation of ethylbenzene with CO2 as soft oxidant

Co₃O₄/γ-Al₂O₃ catalysts with variable Co₃O₄ loadings (5–20 wt%) and deposition of 15% Co₃O₄ on La₂O₃/γ-Al₂O₃ were prepared by wet impregnation method. La₂O₃-γ-Al₂O₃ support with variable composition of La₂O₃ (2–6 wt%) were prepared by co-precipitation method. All the catalysts were tested for oxidative dehydrogenation of ethylbenzene with CO₂ as soft oxidant. Among the Co₃O₄/γ-Al₂O₃ catalysts, 15% Co₃O₄/γ-Al₂O₃ has shown good performance and hence this catalyst has been chosen to investigate the effect of La₂O₃ species. CO₂ pulse chemisorption data indicate more amount of CO₂ uptake over 15% Co₃O₄/4%La₂O₃/γ-Al₂O₃ catalyst which clearly indicates that this catalyst exhibits good performance in ethylbenzene dehydrogenation with CO₂ as soft oxidant because of reverse water gas shift reaction. Temperature programmed reduction studies indicate that the Co₃O₄ catalysts follow two step reduction mechanism from Co₃O₄ to CoO and then to Co and La₂O₃ promotional effect is visible through facile reduction of Co₃O₄ species. La₂O₃ doping has a vital influence in getting enhanced ethylbenzene conversion, styrene yield and alleviates catalyst deactivation compared to that of unpromoted Co₃O₄/γ-Al₂O₃ catalyst. TGA studies indicate the presence low amount coke deposition during time-on-stream over 15% Co₃O₄/4%La₂O₃/γ-Al₂O₃ catalyst compared to 15% Co₃O₄/γ-Al₂O₃ catalyst.     

Beiträge zur Untersuchung anorganischer nichtstöchiometrischer Verbindungen. XXXIII. Darstellung und elektronenmikroskopische Untersuchung von Hf2Nb20O54, M3Nb44O116 und MNb24O62 (M = Zr,Hf)

Contributions to the Investigation of Inorganic Non-stoichiometric Compounds. XXXIII. Preparation and Electron Microscopical Investigation of Hf₂Nb₂₀O₅₄, M₃Nb₄₄O₁₁₆, and MNb₂₄O₆₂ (M = Zr, Hf) The phases Hf₂Nb₂₀O₅₄, Zr₃Nb₄₄O₁₁₆, Hf₃Nb₄₄O₁₁₆, and β-HfNb₂₄O₆₂ have been prepared for the first time. The oxides MO₂ (M = Zr, Hf) and Nb₂O₅ were fused with (NH₄)₂SO₄ and their mixed precipitations were heated at 1350°C. In the same way we also obtained pure β-ZrNb₂₄O₆₂. The new compounds have block structures, as the structure investigation with HRTEM shows. Hf₂Nb₂₀O₅₄ is isostructural with Nb₂₂O₅₄, the same is valid for Zr₃Nb₄₄O₁₁₆ and Hf₃Nb₄₄O₁₁₆ with respect to Nb₄₇O₁₁₆. β-HfNb₂₄O₆₂ has the same structure as β-ZrNb₂₄O₆₂ and β-Nb₂₅O₆₂.     

Reaktionen von Zinnchloriden mit Polysulfiden. Die Kristallstrukturen von (PPh4)2[SnCl2(S6)2], (PPh4)2[Sn4Cl4S5(S3)O] und (PPh4)2[SnCl6] · S8 · 2CH3CN

Reaction of Tin Chlorides with Polysulfides. Crystal Structures of (PPh₄)₂[SnCl₂(S₆)₂], (PPh₄)₂[Sn₄Cl₄S₅(S₃)O], and (PPh₄)₂[SnCl₆] · S₈ · 2CH₃CN . The reaction of PPh₄[SnCl₃] with Na₂S₄ in acetonitrile in the presence of small amounts of water yields (PPh₄)₂[Sn₄Cl₄S₅(S₃)O] and minor amounts of (PPh₄)₂[SnCl₂(S₆)₂], PPh₄Cl · 2S₈ and (PPh₄)₂[SnCl₆]. SnCl₄ is partially reduced by (PPh₄)₂S_x, PPh₄[SnCl₃] and (PPh₄)₂[SnCl₆] · S₈ · 2CH₃CN being produced. According to the X-ray crystal structure determination the [Sn₄Cl₄S₅(S₃)O]^2?-ion consists of an O atom that is coordinated by four Sn atoms which in turn are liked with one another by five single S atoms and one S₃ group. In the [SnCl₂(S₆)₂]^2?-ion the Sn atom is octahedrally coordinated by two Cl atoms in trans arrangement and by two chelating S₆ groups. Octahedral [SnCl₆]^2? ions and S₈ molecules in the crown conformation are present in (PPh₄)₄[SnCl₆] · S₈ · 2CH₃CN.     

Study of Li<Subscript>4</Subscript>Ti<Subscript>5</Subscript>O<Subscript>12</Subscript> interaction with solid lithium-containing electrolytes

Compatibility of the lithium-titanium spinel Li₄Ti₅O₁₂ in contact with precursors of lithium-conducting solid electrolytes of composition Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP), Li_1.5Al_0.5Ge_1.5(PO₄)₃ (LAGP), Li_0.5La_0.5TiO₃ (LLT) was studied. It was found that, in sintering of Li₄Ti₅O₁₂ brought in contact with LATP and LAGP, a solid-phase reaction occurs to give nonconducting phases (TiO₂ and Li₃PO₄). The conductivity of the stable composite Li₄Ti₅O₁₂/LLT (10%) is higher than that of the starting Li₄Ti₅O₁₂, which makes it possible to regard the composite as a promising anode material for lithium-ion batteries.     

The chemistry of chromyl fluoride III. Reactions with inorganic systems

Reactions of CrO₂F₂ with MF or MF₂ gave the corresponding M₂CrO₂F₄ and MCrO₂F₄ fluorochromates. With the Lewis Acids (SO₃, TaF₅, SbF₅) and (CF₃CO)₂O known and new chromyl compounds [CrO₂(CF₃COO)₂, CrO₂(SO₃F)₂, CrO₂FTaF₆, CrO₂FSbF₆, CrO₂FSb₂F₁₁] were produced. Chromyl fluoride and inorganic salts (CF₃COONa and NaNO₃) produced the following complexes - Na₂CrO₂F₂(CF₃COO)₂ and Na₂CrO₂F₂(NO₃)₂. Unusual solid products were obtained with CrO₂F₂ and NO, NO₂, SO₂.A new method of preparing CrO₂F₂ is also presented.     

Syndiotactic polymerization of styrene catalyzed by alkenyl‐substituted cyclopentadienyltitanium trichlorides

CH₂?CHCH₂CpTiCl₃ (1), CH₂?CHCH₂CH₂CpTiCl₃ (2) and CH₃CH₂CH₃CpTiCl₃ (3) have been synthesized and characterized. The influence of the alkenyl substituent groups on the catalyst activities in the syndiotactic polymerization of styrene was investigated. The catalyst activities decreased in the order CH₂?CHCH₂CH₂CpTiCl₃ > CH₃CH₂CH₂CH₂CpTiCl₃ > CH₃CH₂CH₂CpTiCl₃ > CH₂?CHCH₂CpTiCl₃ (Cp?C₅H₄). By using complex 1, the dependence of the activity on the concentration of methylaluminoxane, triisobutylaluminum and diisobutylaluminum hydride was investigated. Copyright © 2003 John Wiley & Sons, Ltd.