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The carbonyl cluster compound [GeRu6(CO)18HI] is unique in regard to its structure and bonding with a GeRu6 cluster core, a planar GeRu4HI unit, extensive multi‐center bonding, and an aromatic ring current similar to benzene (9‐10 nA T−1). The open‐shell cluster core is a Ge‐centered five‐membered Ru4(Ru2) ring with CO ligands and an additional H and I atom, each bridging two Ru atoms on opposite sides of the cluster core. The compound is prepared at 130 °C in a weakly‐coordinating ionic liquid. [ABSTRACT FROM AUTHOR]

The novel tin bromido aluminates [Sn3(AlBr4)6](Al2Br6) (1), Sn(AlBr4)2 (2), [EMIm][Sn(AlBr4)3] (3) and [BMPyr][Sn(AlBr4)3] (4) ([EMIm]: 1‐ethyl‐3‐methylimidazolium, [BMPyr]: 1‐butyl‐1‐methyl‐pyrrolidinium), are obtained from a ionic‐liquid‐based reaction of AlBr3 and SnCl2 or SnBr2, resulting in colorless and transparent crystals. 1 contains a neutral, inorganic ∞3[Sn3(AlBr4)6] network filled with intercalated Al2Br6 molecules. 2 represents a 3D structure isotypic to Pb(AlCl4)2 or α‐Sr[GaCl4]2. 3 and 4 exhibit infinite ∞1[Sn(AlBr4)3]n− chains that are separated by the voluminous [EMIm]+/[BMPyr]+ cations. All title compounds contain Sn2+ coordinated by AlBr4 tetrahedra, resulting in chains or 3D networks. Moreover, all title compounds show photoluminescence due to Br−→Al3+ ligand‐to‐metal charge‐transfer excitation, followed by 5s2p0←5s1p1 emission on Sn2+. Most surprisingly, the luminescence is highly efficient (quantum yield >50 %). Specifically, 3 and 4 exhibit outstanding quantum yields of 98 and 99 %, which are the highest values observed for Sn2+‐based luminescence so far. The title compounds have been characterized by single‐crystal structure analysis, elemental analysis, energy‐dispersive X‐ray analysis, thermogravimetry, infrared and Raman spectroscopy, UV‐Vis and photoluminescence spectroscopy. [ABSTRACT FROM AUTHOR]

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The halogenido stannates(II) [BMIm][Sn3Cl7] and [BMIm][Sn4Br9] are obtained by ionic‐liquid‐based synthesis with SnX2 and [BMIm]X (X=Cl, Br; [BMIm]=1‐butyl‐3‐methylimidazolium) near room temperature (45–50 °C). Both form colorless, moisture‐sensitive crystals and exhibit layered anionic networks. [BMIm][Sn3Cl7] contains "horseshoe"‐like ∞1(SnCl1/1Cl2/2) chains that are linked via [SnCl3]− anions to ∞2[Sn3Cl7]− zigzag‐planes. [BMIm][Sn4Br9] contains a complex ∞2[Sn4Br9]− network with altogether four different crystallographic Sn2+ sites and different coordination. For comparison with these complex halogenido stannates(II), PbCl2/PbBr2 are reacted with similar conditions, which, however, only results in [BMIm][PbCl3] containing ∞1[PbCl3]− chains. Beside the crystal structures, the thermal and optical properties are examined and feature certain emission of visible light for all title compounds at room temperature. Whereas the quantum yields of [BMIm][Sn4Br9] (3 %) and [BMIm][PbCl3] (21 %) are low, [BMIm][Sn3Cl7] shows surprisingly efficient photoluminescence with a quantum yield of 46 %. [ABSTRACT FROM AUTHOR]

Nine Ge−Fe carbonyl cluster compounds are prepared via ionic liquids‐based synthesis. This includes the novel compounds [EMIm][Fe(CO)3I(GeI3)], [EHIm][Fe(CO)3I(GeI3)], [BMIm][GeI2{Fe(CO)4}2(μ‐I)][AlCl4]2, [GeI2{Fe(CO)4}2(μ‐I)][Fe(AlBr4)3], [BMIm]2[(FeI2)0.75{Fe(CO)2I(GeI3)2}2], and [EHIm][Fe(CO)4(GeI2)2Fe(CO)3GeI3] as well as the previously reported compounds (Fe(CO)4(GeI3)2, FeI4{GeI3Fe(CO)3}2, and Ge12{Fe(CO)3}8(μ‐I)4 (EMIm: 1‐ethyl‐3‐methylimidazolium, EHIm: 1‐ethylimidazolium, BMIm: 1‐butyl‐3‐methylimidazolium). With this series of compounds, a comparison of synthesis conditions and structural features is possible and, for instance, allows correlating the composition and structure of the respective Ge−Fe carbonyl cluster compounds with the type and acidity of the ionic liquid. With [EMIm][{GeI3}2Fe(CO)3I], moreover, we can exemplarily show the thermal decomposition as a single‐source precursor in the ionic liquid, resulting in bimetallic Ge−Fe nanoparticles with small size and narrow size distribution (7.0±1.4 nm). [ABSTRACT FROM AUTHOR]

[SnI8{Fe(CO)4}4][Al2Cl7]2 contains the [SnI8{Fe(CO)4}4]2+ cation with an unprecedented highly coordinated, bicapped SnI8 prism. Given the eightfold coordination with the most voluminous stable halide, it is all the more surprising that this SnI8 arrangement is surrounded only by fragile Fe(CO)4 groups in a clip‐like fashion. Inspite of a predominantly ionic bonding situation in [SnI8{Fe(CO)4}4]2+, the I−⋅⋅⋅I− distances are considerably shortened (down to 371 pm) and significantly less than the van der Waals distance (420 pm). The title compound is characterized by single‐crystal structure analysis, spectroscopic methods (EDXS, FTIR, Raman, UV/Vis, Mössbauer), thermogravimetry, and density functional theory methods. [ABSTRACT FROM AUTHOR]

[SnI8{Fe(CO)4}4][Al2Cl7]2 enthält ein [SnI8{Fe(CO)4}4]2+‐Kation mit einem beispiellos hochkoordinierten, zweifach überdachten SnI8‐Prisma. In Anbetracht der achtfachen Koordination mit dem voluminösesten, stabilen Halogenid ist es umso erstaunlicher, dass die SnI8‐Baugruppe nur von fragilen Fe(CO)4‐Gruppen klammerartig umgeben ist. Trotz der überwiegend ionischen Bindungssituation in [SnI8{Fe(CO)4}4]2+ sind die I−⋅⋅⋅I−‐Abstände verkleinert (bis zu 371 pm) und liegen deutlich unter dem Van‐der‐Waals‐Abstand (420 pm). Charakterisiert wurde die Titelverbindung durch Einkristallstrukturanalyse, spektroskopische Methoden (EDXS, FT‐IR, Raman, UV/Vis, Mößbauer), Thermogravimetrie und Dichtefunktionaltheorie. [ABSTRACT FROM AUTHOR]

Dark red and brick red transparent crystals of FeI4{GeI3Fe(CO)3}2 ( 1) and (GeI3)2Fe(CO)4 ( 2) were obtained by reacting GeI4 and Fe2(CO)9 or Fe3(CO)12 in a mixture of [BMIM]Cl and AlCl3 as ionic liquid (BMIm = 1-butyl-3-methylimidazolium). According to X-ray structure analysis based on single crystals, the title compounds exhibit cluster units with Fe-Ge bonds. FeI4{GeI3Fe(CO)3}2 consists of two GeI2I1/2-Fe(CO)3I2/2 units that are interlinked by a distorted octahedral FeI6/2 group. (GeI3)2Fe(CO)4 consists of two GeI3 units that are connected by a square planar Fe(CO)4 group with a linear Ge-Fe-Ge unit. Depending on the synthesis conditions, interestingly, (GeI3)2Fe(CO)4 crystallizes either in P21/ n ( 2a) or in P 1 ( 2b). 2a exhibits a more dense packing, whereas 2b exhibits shorter intermolecular I-I distances. Both title compounds are temperature labile and highly sensitive to oxygen, moisture and illumination, including X-ray irradiation. They decompose with release of CO in absence of certain CO atmosphere. In addition to crystal structure analysis the compounds were characterized by energy dispersive X-ray (EDX) analysis, thermogravimetry (TG) and infrared spectroscopy (FT-IR). [ABSTRACT FROM AUTHOR]

Microemulsions (MEs) are ideal for obtaining high-quality inorganic nanoparticles. As thermodynamically stable systems with a nanometer-sized droplet phase that serves as a nanoreactor, MEs have obvious advantages for the synthesis of nanoparticles. MEs also have disadvantages, such as their complexity as multicomponent systems, the low amount of obtainable nanoparticles, their limited thermal stability, the fact that hydrolyzable or oxidizable compounds are often excluded from synthesis, the partly elaborate separation of nanoparticles, as well as the removal of surface-adhered surfactants subsequent to synthesis. This Review presents some strategies to further expand the options of ME-based synthesis of inorganic nanoparticles. This comprises the crystallization of nanoparticles in 'high-temperature MEs', the synthesis of hollow nanospheres, the use of hydrogen peroxide or liquid ammonia as the polar droplet phase, and the synthesis of base metals and nitrides in MEs. [ABSTRACT FROM AUTHOR]

Mikroemulsionen (ME) sind ideal, um hochwertige anorganische Nanopartikel zu erhalten. Als thermodynamisch stabile Systeme mit einer Phase aus Nanometer‐großen Tröpfchen, die als Nanoreaktoren dienen, bieten sie für die Nanopartikelsynthese eine Reihe an Vorteilen. ME haben aber auch Nachteile, z. B. ihre Komplexität als Mehrkomponentensysteme, die geringe erhältliche Nanopartikelmenge, die begrenzte thermische Stabilität, der häufige Ausschluss hydrolysierbarer oder oxidierbarer Verbindungen von der Synthese, die partiell sehr aufwendige Abtrennung der Nanopartikel sowie die Entfernung Oberflächen‐gebundener Tenside nach der Synthese. Dieser Aufsatz soll einige Strategien zur Erweiterung der ME‐basierten Synthese anorganischer Nanopartikel aufzeigen. Dazu zählen die Kristallisation von Nanopartikeln mittels “Hochtemperatur‐ME”, die Synthese nanoskaliger Hohlkugeln, die Verwendung von H2O2 oder flüssigem NH3 als polare Tröpfchenphasen sowie die Synthese von unedlen Metallen und Nitriden in ME. Nanoreaktoren in Mikroemulsionen sind ideal, um hochwertige anorganische Nanopartikel wie Bimetalle, nanoskalige Hohlkugeln, unedle Metalle, Peroxide oder Metallnitride zu synthetisieren. Dieser Aufsatz beschreibt verschiedene Möglichkeiten jenseits der üblichen Mikroemulsionssynthese von Nanopartikeln. [ABSTRACT FROM AUTHOR]

AgSCN nanoparticles were prepared via a water-in-oil microemulsion approach, using KSCN and AgNO3 as starting materials. The as-prepared AgSCN nanoparticles are readily crystalline, exhibit a uniform spherical shape, and have a mean diameter of 25 nm. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) confirm particle size and size distribution. X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR) prove the phase composition and purity. The particle size can be varied in a range of 25 and 40 nm (according to electron microscopy) by variation of the concentration of AgNO3 (i.e., 2 mL of 0.1 to 0.5 M AgNO3 solution). Optical spectroscopy (UV/Vis) indicates an optical band-gap of 3.78 eV without a size-depending shift at this specific particle size. The microemulsion approach can be extended to obtain further nanoscaled thiocyanates like CuSCN, AuSCN, Hg(SCN)2, and Pb(SCN)2. [ABSTRACT FROM AUTHOR]

A novel modification of potassium nitrate is obtained subsequent to solvothermal reaction and crystallization at reduced temperature from diethylformamid (DEF) as solvent. δ-KNO3 crystallizes with the monoclinic space group P21/ c. Most intriguing is the coordination number of potassium and oxygen as expressed by the Niggli notation δ-K8/8[NO4/4O4/2] that differs from the known modifications of potassium nitrate (α-K9/9[NO9/3], β-K9/9[NO9/3], γ-K9/9[NO9/3]). Moreover, the stacking of the NO3- anions differentiates from the known KNO3 modifications. As only few crystals were obtained, the new modification is characterized by single-crystal structure analysis as well as by Fourier-transformed infrared spectroscopy. The latter reliably points to the presence of nitrate and shows a ν(N-O) vibration centered at 1384 cm-1, but with significantly different shape and band width as compared to α-K9/9[NO9/3] as a reference. [ABSTRACT FROM AUTHOR]

By reacting Mn2(CO)10 and TeI4 in the ionic liquid[BMIm][OTf] (1-butyl-3-methylimidazolium trifluromethanesulfonate), brick-red crystals of [BMIm][(Te2)3{Mn(CO)3}2{Mn(CO)4}3]are obtained. The title compound contains the carbonyl anion[(Te2)3{Mn(CO)3}2{Mn(CO)4}3]-. Herein, three formal Te22- units and two formal Mn(CO)3+ fragments establish a distorted heterocubane-like Te6Mn2 structure. Three edges of this heterocubane are furthermore capped by Mn(CO)4+ fragments. The resulting Te6Mn5 building unit, moreover, looks very similar to the P113- anion - the so-called ufosane. The mean distances Te-Te and Te-Mn are observed with 277.6 and 264.7 pm, respectively. In addition to single-crystal structure analysis, the title compound is characterized by infrared spectroscopy (FT-IR), thermogravimetry (TG) and energy-dispersive X-ray (EDX) analysis. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[bmim]2[{PbMn(CO)5}6I8] is synthesized from a solution of PbI2 and Mn2(CO)10 in [bmim][NTf2] (NTf2: bis‐trifluoromethanesulfonimide) in a glass ampule at 130 °C for 20 d (about 20% yield). [ABSTRACT FROM AUTHOR]