Crystal structure of [Ir(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl]<Subscript>2</Subscript>[OsCl<Subscript>6</Subscript>]Cl<Subscript>2</Subscript>. Crystal-chemical analysis of the iridium-osmium system

The [Ir(NH₃)₅Cl]₂[OsCl₆]Cl₂ binary complex salt has been prepared, and its structure was investigated by single crystal X-ray diffraction. Crystal data: a = 11.1901(13) Å, b = 7.9138(13) Å, c = 13.4384(18) Å; β = 99.640(3)°, V = 1190.0(2), space group C2/m, Z = 2, FW = 1099.47, d _x = 3.068 g/cm³. Thermolysis products of [Ir(NH₃)₅Cl]₂[OsCl₆]Cl₂, [Ir(NH₃)₅Cl][OsBr₆], (NH₄)₂[OsCl₆]_x[IrCl₆]_1?x , and K₂[OsCl₆]_x[IrCl₆]_1?x were studied by X-ray phase analysis; the unit cell parameters were refined, and the dependence of volume per atom (V/Z) on the composition of the Ir Os_1?x solid solution has been plotted.     

Synthesis of nonequilibrium Ir<Subscript>x</Subscript>Re<Subscript>1-x</Subscript> solid solutions. Crystal structure of [Ir(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl]<Subscript>2</Subscript>[ReCl<Subscript>6</Subscript>]Cl<Subscript>2</Subscript>

Synthesis of five binary complex salts with an [Ir(NH₃)₅Cl]²⁺ complex cation is described. The counterions are [ReCl₆]^2–, [IrCl₆]^2–, [ReBr₆]^2–, and Cl^–. A polycrystal X-ray diffraction study has been performed for [Ir(NH₃)₅Cl]₂[ReCl₆]Cl₂, and its crystal structure has been determined. A series of Ir _x Re_1–x phases (0.5 x > 1) were obtained by reductive thermolysis. For the Ir-Re system, the history of the V/Z(x) dependence has been refined.Original Russian Text Copyright © 2004 by S. A. Gromilov, S. V. Korenev, I. V. Korolkov, K. V. Yusenko, and I. A. BaidinaTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 508–515, May–June 2004.     

Pseudohexagonal motif of the arrangement of compex anions in the structure of [Ru(NH3)5Cl]2[Re6S8(CN)6]·3H2O

The [Ru(NH₃)₅Cl]₂[Re₆S₈(CN)₆]·3H₂O salt was obtained; its crystal structure was analyzed: a = 10.7713(9) Å, b = 13.9602(11) Å, c = 14.7956(11) Å, α = 91.961(3)°, β = 109.985(3)°, γ = 110.030(3)°, V = 1935.3(3) ų, space group P1ˉ, Z = 2, d _calc = 3.441 g/cm³. In the cluster anion, the Re-Re distances lie in the range from 2.594 Å to 2.612 Å. For two crystallographically independent complex cations, Ru-N_av is 2.105 Å, and Ru-Cl_av 2.329 Å. A pseudohexagonal motif of the structure was found. Original Russian Text Copyright ? 2008 by K. V. Yusenko, I. A. Baidina, E. A. Shusharina, and S. A. Gromilov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 1, pp. 178–181, January–February, 2008.     

Substituent‐Free Gallium by Hydrogenolysis of Coordinated GaCp*: Synthesis and Structure of Highly Fluxional [Ru2(Ga)(GaCp*)7(H)3]

All change : Complete ligand exchange through the hydrogenation of [Ru(η⁴‐cod)(η⁶‐cot)] in the presence of GaCp* under mild conditions leads to the title complex featuring a “naked” gallium atom bridging two ruthenium centers (see structure: C white, Ga blue, Ru red). This cluster can be considered as a trapped intermediate on the way to mixed‐metal nanoparticles; cot=1,3,5‐cyclooctatriene; cod=1,5‐cyclooctadiene, Cp*=C₅Me₅.

     

Cover Picture: Substituent‐Free Gallium by Hydrogenolysis of Coordinated GaCp*: Synthesis and Structure of Highly Fluxional [Ru2(Ga)(GaCp*)7(H)3] (Angew. Chem. Int. Ed. 21/2009)

Soft skin, hard core …? is the basic principle for the formation of a nano‐alloy from molecular precursors. The co‐hydrogenolysis of ruthenium complexes in presence of GaCp* gives the isolable key intermediate [Ru₂(Ga)(GaCp*)₇(H)₃] featuring a substituent‐free bridging gallium atom. From this “embryonic” species Ru/Ga phases are formed by complete cleavage of the protective Cp* shell (depicted as an eggshell in the Cover picture), as described by R. A. Fischer et al. in their Communication on page 3872 ff.

     

Chemistry of SURMOFs: layer-selective installation of functional groups and post-synthetic covalent modification probed by fluorescence microscopy

Layer-selective installation of functional groups at SURMOFs (surface-attached metal-organic framework multilayers) is reported. Multilayers of [Cu(ndc)(dabco)(0.5)] grown in [001] orientation on pyridine-terminated organic self-assembled monolayers on Au substrates were functionalized with amino groups by step-by-step liquid-phase epitaxy. The method allows the growth of samples exhibiting one monolayer of functional groups at the external thin-film surface. In situ quartz crystal microbalance monitoring confirmed the presence of amino groups by turning the multilayer film from a non-reactive to a reactive material for covalent binding of fluoresceinisothiocyanate, and fluorescence microscopy displays the expected luminous property.     

Synthesis and Structure of Binary Complexes of Platinum Group Metals — Precursors of Metallic Materials

This paper reviews the results of structural studies of binary complexes whose cationic part contains cobalt, rhodium, iridium, ruthenium, and chromium chloropentammne. The structure of these compounds is discussed in the light of the design of new multicomponent precursor compounds. Data are given on the chemical and phase compositions of the polymetallic powders resulting from the thermal decomposition of the compounds studied.     

Formation Mechanism of a Nano-Ring of Bismuth Cations and Mono-Lacunary Keggin-Type Phosphomolybdate

A new hetero-bimetallic polyoxometalate (POM) nano-ring was synthesized in a one-pot procedure. The structure consists of tetrameric units containing four bismuth-substituted monolacunary Keggin anions including distorted [BiO₈] cubes. The nano-ring is formed via self-assembly from metal precursors in aqueous acidic medium. The compound (NH₄)₁₆[(BiPMo₁₁O₃₉)₄] ⋅ 22 H₂O; (P₄Bi₄Mo₄₄) was characterized by single-crystal X-ray diffraction, extended X-ray absorption fine structure spectroscopy (EXAFS), Raman spectroscopy, matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF), and thermogravimetry/differential scanning calorimetry mass spectrometry (TG-DSC-MS). The formation of the nano-ring in solution was studied by time-resolved in situ small- and wide-angle X-ray scattering (SAXS/WAXS) and in situ EXAFS measurements at the Mo−K and the Bi−L₃ edge indicating a two-step process consisting of condensation of Mo-anions and formation of Bi−Mo-units followed by a rapid self-assembly to yield the final tetrameric ring structure.