Unexpectedly facile isomerisation of [7,10-Ph2-7,10-nido-C2B10H10]2- to [7,9-Ph2-7,9-nido-C2B10H10]2-

The 2e-reduction of 1,12-Ph2-1,12-closo-C(2)B(10)H(10) followed by oxidation or metallation gives products that arise from [7,9-Ph2-7,9-nido-C(2)B(10)H(10)](2-), formed by unexpectedly facile isomerisation of the kinetic 7,10-isomer: the 4,1,6-MC(2)B(10) compounds which result are progressively isomerised to 4,1,8- and 4,1,12-isomers for M = {CpCo} but to an equilibrium mixture of 4,1,8- and 4,1,12-isomers for M = {(arene)Ru}.     

The structures of MeP(C2B10H10)2CH2 and MeAs(C2B10H10)2, compounds containing o-carborane ring carbon atoms in the heterocycle

Conclusions Crystal and molecular structures have been determined for 1-methylphospha-2,3,5,6-bis-o-carboranocyclohexane and 1-methylarsa-2,3,4,5-bis-o-carboranocyclopentane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1523–1528, July, 1979.     

Metalloktaederdoppel in den Clusterverbindungen Gd10I16(C2)2 und Gd10Br15B2/Tb10Br15B2

Gd₁₀I₁₆(C₂)₂ and Gd₁₀Br₁₅B₂/Tb₁₀Br₁₅B₂ Cluster Compounds with M₁₀ Twin Octahedra The compound Gd₁₀I₁₆(C₂)₂ can be prepared from Gd metal, GdI₃ and C at 950 °C. It crystallizes in P1 with a = 10.463(4) Å, b = 16.945(6) Å, c = 11.220(4) Å, α = 99.15(3)°, β = 92.68(3)° und γ = 88.06(3)°. Gd₁₀Br₁₅B₂ is formed between 900 und 950 °C, Tb₁₀Br₁₅B₂ between 900 und 930 °C from stoichiometric amounts of the rare earth metals, tribromide and boron. Both compounds crystallize in the space group P1 for Gd₁₀Br₁₅B₂ with a = 8.984(2) Å, b = 9.816(2) Å, c = 10.552(5) Å, α = 91.14(3)°, β = 114.61(3)° and γ = 110.94(3)° and for Tb₁₀Br₁₅B₂ with a = 8.939(4) Å, b = 9.788(3) Å, c = 10.502(2) Å, α = 91.19(3)°, β = 114.51(3)° and γ = 111.10(2)°. In the crystal structures of all three compounds the rare earth metals form edge‐shared Ln₁₀ twin octahedra. In Gd₁₀I₁₆(C₂)₂ the Gd octahedra are centered with C₂ groups (d_C–C = 1.43(7) Å). In Ln₁₀Br₁₅B₂ (Ln = Gd, Tb) the octahedra contain single boron atoms. The clusters are connected through halide atoms to chains [Ln₁₀(Z)₂X X X ]. Adjacent chains are fused threedimensionally via I I for the Gd iodide carbide and via Br Br for the bromide borides of Gd und Tb. It is interesting to see an identical pattern of connection between the chains for the reduced oxomolybdates, e. g. PbMo₅O₈.     

Hydrogen bonding and structure of Ba2Ru2Cl10O·10H2O

Dibarium μ‐oxido‐bis[pentachloridoruthenate(IV)] decahydrate, Ba₂Ru₂Cl₁₀O·10H₂O, has been prepared from ruthenium(III) chloride and barium chloride in hydrochloric acid. It crystallizes in the monoclinic system (space group C2/c). The structure consists of alternating layers of [Ru₂Cl₁₀O]⁴⁻ and [Ba(H₂O)₇]²⁺ complex ions along the a direction. The O atom bonded to ruthenium occupies the 4e site, with symmetry, while the other atoms occupy general 8f sites. The overall structure is held together by O—H...O hydrogen bonds and O—H...Cl dipole–dipole interactions.     

SO 2 sorption properties of fly ash zeolites

In the presented study, the sulfur dioxide sorption properties of fly ash zeolite X were investigated. Sorption tests were performed on fly ash zeolite samples that were not prepared specially for sorption, in addition to dried samples and samples in the presence of water vapor. The samples saturated with water vapor showed the highest sorption capacity. The sorption capacity of the samples additionally dried prior to the sorption experiment was higher than that of the samples that were not specially prepared for the sorption test. Regeneration tests indicated relatively good regeneration properties. The obtained results were described with the use of Langmuir, Sips, and Dubinin–Astakhov models, with the Dubinin–Astakhov model providing the best fit.     

Crystal structures of CrH2P3O10 and InH2P3O10

The crystal structures of chromium and indium dihydrogen triphosphates, CrH₂P₃O₁₀ and InH₂P₃O₁₀, in modification II are refined by the Rietveld method using X-ray powder diffraction data. The compounds crystallize in the monoclinic crystal system, space group P21/n. Z = 4, a = 7.3225(4)Å, b = 8.6835(6)Å, c = 11.6599(7) Å, and b = 102.388(3)° for CrH₂P₃O₁₀, and a = 7.5332(1)Å, b = 9.0841(1)Å, c = 11.8600(1) Å, and b = 103.9596(7)° for InH₂P₃O₁₀. The structures are refined in the isotropic approximation (pseudo-Voigt profile function): R_p = 4.8%, R_wp = 6.9%, R_Bragg = 7.5%, R_F = 9.9% for CrH₂P₃O₁₀; R_p = 6.3%, R_wp = 8.3%, R_Bragg = 6.2%, R_F = 4.1% for InH₂P₃O₁₀. The crystal structures of compounds in the isostructural series M^IIIH₂P₃O₁₀-II, where M^III = Al, Ga, Cr, V, Fe, and In, are examined and compared.     

Li2AlB5O10

A new compound, dilithium aluminium pentaborate, Li₂Al­B₅O₁₀, has been synthesized by solid‐state reaction and its structure determined by single‐crystal X‐ray diffraction. This compound is composed of [B₅O₁₀]^5? groups linked by AlO₄ tetrahedra. The [B₅O₁₀]^5? group consists of two hexagonal B–­O rings perpendicular to each other connected by tetracoordinated boron. All the B–O rings in this structure can be divided into two groups, with one group approximately parallel and the other perpendicular to the c axis.     

A macrocycle-assisted nanoparticlization process for bulk Ag2S

We report herein a new nanoparticlization process for the bulk-to-nano transformation of Ag₂S by incorporating both top-down and bottom-up approaches. Bulk Ag₂S was dissolved in solution with the assistance of a macrocyclic ligand, hexamethylazacalix[6]pyridine (Py[6]), to produce polynuclear silver sulfide cluster aggregates. All Ag–S cluster aggregates obtained in three crystalline complexes were protected by Py[6] macrocycles. Removing the protective Py[6] macrocycles by protonation led to the generation of unconventional Ag–S nanoparticles with a large energy gap. Theoretical calculations by a hybrid DFT method demonstrated that the silver sulfide clusters with high Ag/S ratio exhibited more localized HOMO–LUMO orbitals, which consequently enlarged their band gap energies. These experimental and theoretical studies broaden our understanding of the fabrication of nanomaterials by virtue of the advantages of both bottom-up and top-down methods and meanwhile provide a viable means of adjusting the band gap of binary nanomaterials independent of their size.     

C-10 substituted 19-norsteroids—VII 10-cyano-2-ketosteroids

The syntheses of 10- and 10β-cyano-5-estran-2-one-17β-ol is described. Some reactions of the new compounds are described and discussed.