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1.
The compound [K(18‐crown‐6)]8[Ge9=Ge9=Ge9=Ge9] ˙ 8en ( 1 ) featuring a [Ge9=Ge9=Ge9=Ge9]8‐cluster anion was synthesized from K4Ge9 for the first time. The X‐ray single crystal analysis shows that, in many respects such as bond connection and packing style, compound 1 is quite different from the previously reported compounds [Rb(18‐crown‐6)]8[Ge9=Ge9=Ge9=Ge9] ˙ 2en ( 2 ) and [Rb(18‐crown‐6)]8[Ge9=Ge9=Ge9=Ge9] ˙ 6en ( 3 ). Crystal packing of 1 gives strong indications that the highly charged nano‐rods self assembly in a hexagonal rod packing.  相似文献   

2.
Ugrinov A  Sevov SC 《Inorganic chemistry》2003,42(19):5789-5791
A tetramer of nine-atom deltahedral germanium clusters and charge 8-, [Ge9=Ge9=Ge9=Ge9]8- , has been characterized as a (Rb-18C6)(+) salt (18C6 = 18-crown-6 polyether). The clusters are connected by pairs of parallel bonds, and the electrons are delocalized over the whole anion. The size of the tetramer is of nanorod dimensions, ca. 2 nm.  相似文献   

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Deep‐red moisture and air sensitive single crystals of K4Ge9 were obtained by reacting GeO2 and elemental Ge with metallic W and K at high temperature in a niobium ampoule. The crystal structure of the compound was determined by single crystal X‐ray diffraction experiments. K4Ge9 crystallizes in a polar space group R3c (No. 161), Z = 4 with a = 21.208(1) and c = 25.096(2) Å. The compound contains discrete Ge94? Wade's nido‐clusters which are packed according to a hierarchical atom‐to‐cluster replacement of the Cr3Si prototype and are separated by K+ cations. Two independent [Ge9]4? clusters A (at Cr positions) and B (at Si positions) are found with a ratio A:B = 3:1. The B ‐type cluster satisfactorily represents orientational disorder around the three‐fold axis.  相似文献   

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The title anion was synthesized by oxidation of nido-Ge94- with Ph3P or Ph3As in ethylenediamine solution. It was structurally characterized in the compound (Rb-2,2,2-crypt)6[Ge9=Ge9=Ge9].3en (2,2,2-crypt = 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) crystallized from the solution. The anion is a linear trimer of nine-atom clusters with the shape of tricapped trigonal prisms elongated along two of the three prismatic edges. Each pair of clusters is connected by two exo-bonds.  相似文献   

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La11Ge4In5.00Li1.00 and Ce11Ge5.96In4.04 are prepared from the elements (Nb tubes, 1080 °C for 5 h and 750 °C for 2 d) and characterized by powder and single crystal XRD, and TB‐LMTO‐ASA computations.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

10.
Treatment of GeCl2 · dioxane with the Grignard reagent RMgBr (R = 2,5-tBu2C6H3) furnishes the tetraaryldigermene R2GeGeR2 (4). The X-ray structure analysis of 4 reveals a long GeGe double bond of 236.4 pm and the largest trans-bending angles of the substituents (42.6° and 37.2°) observed so far. The reaction of hexa-2,4-diyne with the germylene R2Ge: (R = 2-tBu-4,5,6-Me3C6H) yields red crystals of the acetylene-bridged bis(germaethene) (Me)R2GeC-CC-CGeR2(Me) 7, the red colour of which indicates conjugation between the two double bonds.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

12.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

13.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

14.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.  相似文献   

15.
Zusammenfassung Der Germanat-Zeolith Ag3HGe7O16·4 H2O wird durch Ionenaustausch aus dem isotypen Ammonium-Zeolith hergestellt. Nach Dehydratation des Ag-Zeoliths bildet sich bei 460°C das zuMe 4Ge9O20 (Me=Na, K) isotype Ag4Ge9O20. Durch Erhitzen auf 650°C entsteht das zuMe 2Ge4O9 (Me=Na, K, Rb, Tl) isotype Ag2Ge4O9. Oberhalb 760°C erfolgt unter Dissoziation die Bildung von metallischem Silber und GeO2 (Rutilform).
The zeolithic germanate Ag3HGe7O16·4 H2O has been prepared by ion-exchange from the analogous ammonium compound. After dehydration at 460°C Ag4Ge9O20 is formed, which is isostructural withMe 4Ge9O20 (Me=Na, K). By heating up to 650°C Ag2Ge4O9 is obtained, having the structure ofMe 2Ge4O9 (Me=Na, K, Rb, Tl). Above 760°C the compound decomposes into silver, oxygen and GeO2 (rutile).


Mit 1 Abbildung  相似文献   

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Formation of Compounds in the Quasi-binary Systems AcX4? MX2 (Ac = Th, U; M = Ca, Sr, Ba, Eu, Ge, Sn, Pb; X = Br, I) T,x-phase diagrams of the systems ThI4? SnI2, ThI4? PbI2, ThI4? CaI2, and ThI4? SrI2 were established using thermoanalysis and x-ray methods. The only ternary compounds have a 1:1 composition. Further AcMX6 compounds (Ac: Th, U; M: Ca, Sr, Ba, Eu, Ge, Sn, Pb; X: Br, I) were synthesized and their structures investigated. Four structure types are found depending on the temperature and the Ac/M combinations. The structures of γ-ThSnI6 and β-ThSnI6 were determined with single crystal methods as representatives of a whole series of isotypic compounds.  相似文献   

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Clusters XY2Z species are theoretically investigated with density functional theory (DFT) method. The results show that for LiP2C, LiAs2Ge and KAs2C species, the C2v isomer is the most stable planar structure, while for other species the Cs isomer is the most stable planar structure at the B3LYP/6-311+G* level. Wiberg Bond Index (WBI) and Nucleus-Independent Chemical Shift (NICS) values indicate the existence of delocalization in stable planar structures. A detailed Molecular Orbital (MO) analysis further reveals that planar isomers of these species have strong aromatic character, which strengthens the structural stability and makes them closely connect with the concept of aromaticity.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.  相似文献   

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