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  • 1
    ISSN: 1434-1948
    Keywords: Tin ; Silicon ; Chalcogens ; Cluster compounds ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of tin(II) chloride with RNa(THF)2 (R = tBu3Si) in THF at -30 °C led to a complex reaction mixture, from which the compounds R4Sn4(THF)2, R2SnSnR2 (5), R-R (7), and a brownish black compound 6 were isolated. In toluene as solvent, the zwitterionic distannene 5 was obtained together with 7 and 6 which upon treatment with Et3PX, furnished the cluster compounds (RSnX)4 (10: × = Se; 11: × = Te). The X-ray structure analyses of the isotypic compounds 10 and 11 revealed that the tin atoms occupy the corners of an undistorted tetrahedron with weak tin-tin interactions. The chalcogen atoms form a plane which bisects the Sn4 tetrahedron.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0044-8249
    Keywords: Germaniumverbindungen ; Enantiomerentrennung ; Trigermane ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0044-8249
    Keywords: Elektronenlokalisierung ; Germaniumverbindungen ; Siliciumverbindungen ; Zintl-Phasen ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 1717-1720 
    ISSN: 0044-2313
    Keywords: Dipotassium Sodium Diantimonidoindate ; K2Na[InSb2] ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Dikalium-Natrium-Diantimonidoindat, K2Na[InSb2], eine Verbindung mit dem Polyanionen ∞2[In2Sb2Sb4/2]6-.Die neuartige Verbindung K2Na[InSb2] bildet sich aus den Elementen bei 900 K in geschlossenen Niobampullen als silbrig glänzende plättchenförmige Kristalle. Die Verbindung ist sehr empfindlich gegen Luft und Feuchtigkeit. Die Kristallstruktur von K2NaInSb2 (Raumgruppe Cmca, No. 64, a = 14,032(2), b = 16,399(3), c = 7,009(1) Å; Z = 8; Pearsonsymbol oC48) wurde an Einkristallen bestimmt. Die Struktur enthält Paare kantenverknüpfter InSb4-Tetraeder, welche über gemeinsame Ecken zu einer zweidimensionalen anionischen infin;2[In2Sb2Sb4/2]6--Teilstruktur verknüpft sind. Die resultierenden Paare tetraedrischer Lücken sind mit Na-Kationen gefüllt. Die [In2Sb2Sb4/2]6--Schichten sind entlang der b-Achse über K-Kationen miteinander verbunden. Die gesamte Struktur kann als Ordnungsvariante der KMnP-Struktur (PbFCl-Typ) angesehen werden.
    Notes: The novel compound K2Na[InSb2] was synthesized from the elements at 900 K in sealed niobium ampoules. The compound forms plate-like crystals with silver metallic luster, which are very unstable in air and moisture. The crystal structure of K2NaInSb2 has been determined using single-crystal X-ray diffraction methods (space group Cmca (No. 64); a = 14.032(2), b = 16.399(3), c = 7.009(1) Å; Z = 8; Pearson symbol oC48). The structure contains pairs of edge-sharing InSb4 tetrahedra which are linked to four other pairs via common vertices and form a two-dimensional ∞2[In2Sb2Sb4/2]6- anionic partial structure. The resulting pairs of tetrahedral holes are filled by Na+ cations. These [In2Sb2Sb4/2]6- layers are stacked along the b-axis and are interconnected by K+ cations. The whole structure can be considered as an ordered derivative of the KMnP structure (PbFCl type).
    Additional Material: 2 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1081-1086 
    ISSN: 0044-2313
    Keywords: K2Mn[P2S6], Hexathiodiphosphate(IV) ; Hexathiohypodiphosphate ; Crystal Structure ; Vibrational Spectrum ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Kristallstruktur und Schwingungsspektrum von Dikaliummangan(II)-hexathiodiphosphat(IV), K2Mn[P2S6]K2Mn[P2S6] wurde aus den Elementen bei 1 173 K in evakuierten Quarzampullen dargestellt. Die Verbindung bildet transparente, hellbraune, luft- und feuchtigkeits-beständige Kristalle. Die Kristallstruktur von K2Mn[P2S6] (monoklin; Raumgruppe P21/n, No. 14; a = 6,1966(9), b = 12,133(2), c = 7,424(1) Å, β = 101,52(1)°; Z = 2; Pearson-Code mP22) enthält Säulen flächenverknüpfter S6-Polyeder (verzerrte Oktaeder und trigonale Antiprismen), die parallel zur a-Achse verlaufen und durch K+ (KZ 10; d(K—S) = 3,23-3,92 Å) miteinander verbunden sind. Die S6-Polyeder der Säulen werden alternierend durch Mn (in Oktaedern mit d̄(Mn—S) = 2,647 Å) bzw. P2-Paare (in trigonalen Antiprismen) zentriert, die zur a-Achse um 73,1° geneigt sind. Die Bindungslängen in den Hexathiodiphosphat(IV)-Anionen [P2S6]4- mit angenäherter 3 2/m-D3d-Symmetrie betragen d̄(P—P) = 2,211 und d̄(P—S) = 2,018 Å. K2Mn[P2S6] ist isotyp zu K2Fe[P2S6] und der zweite Vertreter dieses Strukturtyps. Die beobachteten Fundamentalschwingungen von K2Mn[P2S6] stehen im Einklang mit der Faktorgruppenanalyse und werden auf der Basis von [P2S6]4--Einheiten unter Berücksichtigung der Abweichung von der D3d-Symmetrie zugeordnet.
    Notes: K2Mn[P2S6] was synthesized from the elements in sealed quartz ampoules at 1 173 K. The compound forms transparent light brown crystals, stable against air and moisture. The crystal structure (monoclinic; space group P21/n, No. 14; a = 6.1966(9), b = 12.133(2), c = 7.424(1) Å, β = 101.52(1)°, Z = 2; Pearson code mP22) consists of columns of face-sharing S6 polyhedra (distorted octahedra and trigonal antiprisms) parallel to the a axis, interconnected by inserted K+ (CN 10; d(K—S) = 3.23-3.92 Å). The S6 polyhedra of the columns are centered alternately by Mn (in octahedra with d̄(Mn—S) = 2.647 Å) and P2 pairs (in trigonal antiprisms) which are inclined to the a axis by 73.1°. The bond lengths in the resulting hexathiodiphosphate(IV) anions, [P2S6]4-, with approximate 3 2/m-D3d symmetry, are d(P—P) = 2.211 Å and d(P—S) = 2.018 Å. K2Mn[P2S6] is isotypic to K2Fe[P2S6], being the second member of this structure type. The internal modes of the observed Raman and FIR/IR spectra of K2Mn[P2S6] are in accord with the factor group analysis, and the fundamentals are assigned on the basis of [P2S6]4- units, taking into account the deviation of the D3d symmetry.
    Additional Material: 5 Ill.
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  • 6
    ISSN: 0044-2313
    Keywords: Staffed Clathrate-II ; K21-δNa2+δIn39 ; Indium Cluster Framework ; Synthesis ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: K21-δNa2+δIn39 (δ = 2.8): Eine Cluster-substituierte Clathrat-II Struktur mit einem M136-AlkalimetallnetzK21-δNa2+δIn39 mit δ = 2,82 wurde aus den Elementen in geschlossenen Niobampullen als silbrigglänzende, prismatische Kristalle dargestellt (aufgeschmolzen bei 973 K; getempert bei 623 K). Die Verbindung ist sehr empfindlich gegen Luft und Feuchtigkeit. Die Kristallstruktur von K21-δNa2+δIn39 (orthorhombisch, Raumgruppe Pnma; No. 62; a = 17,844(5) Å, b = 17,192(3) Å, c = 25,078(7) Å; Z = 4; Pearson-Code oP248; δ = 2,82 aus der Strukturverfeinerung) enthält pro Elementarzelle acht leere ikosaedrische In12ico - Cluster (Typ A mit 12 und Typ B mit 7 Exo-Bindungen) und vier von K zentrierte offene In15-Cluster (15 Exo-Bindungen), die Teile von C-Einheiten sind. Die C-Einheiten sind Heterocluster [K(Na2M3In15)] mit M = K + Na. Die räumliche Verteilung der In12ico-Ikosaeder A, B und der Heterocluster C entspricht der Atomverteilung in der kubischen Laves-Phase MgCu2: MgCu2 ≙ [K(Na2M3In15)][In12ico]2. Sämtliche Inn-Cluster sind durch kovalente Exo-Bindungen zu einem 3D-Netzwerk miteinander verbunden (d(In—In) = 2,832 - 3,301 Å). Die restlichen Alkalimetallatome bilden ein M136-Netzwerk vom Clathrat-II-Typ, dessen 16 + 8 Käfige die In12ico-Ikosaeder und [K(Na2M3In15)]-Cluster einhüllen. Die Struktur kann als eine Cluster-substituierte Clathrat-II-Struktur beschrieben werden: (H2)16(CCl4)8(H2O)136 ≙ [In12ico]16[K(M5In15)]8M136. Sie ist ein Vertreter einer neuartigen hierarchischen Strukturfamilie auf der Basis von Cluster-Substitution. Bindungsverhältnisse und strukturelle Zusammenhänge mit anderen Phasen werden diskutiert.
    Notes: K21-δNa2+δIn39 with δ = 2.82 was synthesized (melted at 973 K, annealed at 623 K) from the elements in sealed niobium ampoules. The compound forms prismatic crystals with silver metallic lustre and is unstable in air and moisture. The crystal structure of K21-δNa2+δIn39 (orthorhombic; space group Pnma, No. 62; a = 17.844(5) Å, b = 17.192(3) Å, c = 25.078(7) Å; Z = 4; Pearson code oP248; δ = 2.82, obtained from the structure refinement) contains eight empty In12ico icosahedra of two types, A (12 exo-bonds) and B (7 exobonds), and four open In15 clusters (15 exo-bonds). The latter are centered by K atoms and belong to C units, which are defined as [K(Na2M3In15)] heteroatomic clusters (M = K + Na). The spatial distribution of the In12ico icosahedra A, B and heteroatomic clusters C is that of the atoms in the cubic Laves phase MgCu2: MgCu2 ≙ [K(Na2M3In15)][In12ico]2. All the Inn clusters are interconnected by exo-bonds forming a covalent three-dimensional framework (d(In—In) = 2.832 to 3.301 Å). The remaining alkali metal atoms build up a three-dimensional M136 network of the clathrate-II type with (16 + 8) cages, which envelopes the In12ico icosahedra and [K(Na2M3In15)] clusters. This structure can be described as a cluster-replacement derivative of the clathrate-II structure: (H2S)16(CCl4)8 · (H2O)136 ≙ [In12ico]16[K(M5In15)]8M136, and is one member of a novel hierarchical structure family, based upon cluster-replacement. The bonding as well as the structural relationships to other phases are discussed.
    Additional Material: 6 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 20 (1981), S. 33-51 
    ISSN: 0570-0833
    Keywords: Bond theory ; Main group elements ; Cluster compounds ; Metal-metal interactions ; Solid-state reactions ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Clusters of main group elements are not rare. On the contrary, it is becoming difficult to avoid the discovery of new substances of this type. Clusters are the natural intermediate stages between an element and its isolated atoms or ions. In the form of polycations and polyanions they offer models for the stepwise oxidation and reduction of an element and represent a bridge between the elements. The great majority of homonuclear bonded structures are already present in the solid phases of simple systems. Mobilization of these clusters as molecules represents a great challenge.
    Additional Material: 16 Ill.
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  • 8
    ISSN: 0044-2313
    Keywords: LiMg[BN2] ; Ba4[BN2]2O ; Nitridoborates ; Linear Anions [BN2]3- ; Crystal Structure ; Vibrational Spectrum ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ternary Nitridoborates. 1. LiMg[BN2] and Ba4[BN2]2O, Compounds with the Anion [N—B—N]3-: Syntheses, Crystal Structures, and Vibrational SpectraLiMg[BN2] and Ba4[BN2]2O were synthesized from stoichiometric mixtures of the binary components Li3N, Mg3N2, BN and BaO, Ba3N2. BN in sealed niobium ampoules at 1575 and 1350 K, respectively. The structures are characterized by isolated anions [N—B—N]3-, packed in different ways (LiMg[BN2]: I4/mmm (No. 139); a = 379.8 pm, c = 891.6 pm, c/a = 2.348; Z = 2; Ba4[BN2]2O; Cmca (No. 64); a = 1575.3 pm, b = 729.1 pm, c = 731.9 pm; Z = 4). The bond lengths and the bond angles are d(B—N) = 133.6 pm and β(N—B—N) = 180° in LiMg[BN2] and d(B—N) = 135 pm and β(N—B—N) = 173.4° in Ba4[BN2]2O, respectively.The vibrational spectra have been interpreted with respect to the D∞h symmetry of the isolated [N—B—N]3- anions, taking into account the slight symmetry reduction to C2v in Ba4[BN2]2O. The calculated valence force constants f(B—N) = 8.16 Ncm-1 and f(B—N) = 7.55 Ncm-1 are discussed and compared with those of other nitridoborates.
    Notes: LiMg[BN2] und Ba4[BN2]2O bilden sich aus stöchiometrischen Gemengen der binären Komponenten Li3N, Mg3N2, BN bzw. BaO, Ba3N2, BN in verschweißten Nb-Ampullen bei 1575 bzw. 1350 K. Die charakteristischen Bauelemente sind isolierte [N—B—N]3- -Anionen, die im Kristall unterschiedlich gepackt sind (LiMg[BN2]: I4/mmm (Nr. 139); a = 379.8 pm, c = 891.6pm, c/a = 2.348; Z = 2; Ba4[BN2]2O: Cmca (Nr.64); a = 1575.3 pm, b = 729.1pm, c = 731.9 pm; Z = 4). Die Bindungslängen und Bindungswinkel betragen d(B—N) = 133.6 pm und β(N—B—N) = 180° in LiMg[BN2] bzw. d(B—N) = 135 pm und β(N-B-N) = 173.4° in Ba4[BN2]2O.Die Schwingungsspektren der Verbindungen wurden auf der Basis der D∞h-Symmetrie der isolierten [N—B—N]3--Anionen unter Berücksichtigung der Symmetrieerniedrigung nach C2v in Ba4[BN2]2O interpretiert. Die aus den gemessenen Frequenzen berechneten Kraftkonstanten f(B—N) = 8.16 bzw. 7.55 Ncm-1 werden diskutiert und mit denen anderer Nitridoborate verglichen.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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