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  • 1
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 2
    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.
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  • 3
    ISSN: 0044-2313
    Keywords: Tetrapotassium biphosphidoberyllate, -biarsenidoberyllate, -biantimonidoberyllate ; crystal structure ; vibrational spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: K4BeP2, K4BeAs2, and K4BeSb2 Compounds with Linear [BeX2]4- Anions (X = P, As, Sb)The title compounds are synthesized from the elements. K4BeP2 and K4BeAs2 are isostructural and crystallize trigonal rhombohedrally in the space group R3m (No. 166) with Z = 3. The partial structure of the potassium atoms corresponds to a closest packing of rotational ellipsoides, which envelope an elongated K14-polyhedron (combination of rhombohedron and hexagonal prism). The polyhedrons are filled with linear [BeX2]4- anions, which are the analoga to BeCl2 molecules. The bond lengths are: d(Be—P) = 198.2 pm and d(Be—As) = 206.0 pm. IR spectra confirm the presence of [Sb—Be—Sb]4- anionic groups in K4BeSb2, which crystallizes in the hexagonal system with Z = 2. The vibrational spectra of the compounds are measured. The assignment of the observed frequencies is based on the D∞h symmetry of an isolated [X—Be—X]4- unit.
    Notes: Die Titelverbindungen wurden aus den Elementen dargestellt. K4BeP2 und K4BeAs2 sind isotyp und kristallisieren trigonal-rhomboedrisch in der Raumgruppe R3m (Nr. 166) mit Z = 3. Die Teilstruktur der Kaliumatome entspricht einer dichtesten Packung von Rotationsellipsoiden, welche ein gestrecktes K14-Polyeder (Kombination von Rhomboeder und hexagonalem Prisma) einhüllen. Die Polyeder sind durch lineare [BeX2]4--Anionen aufgefüllt, Analoga des BeCl2-Moleküls. Die Bindungslängen sind d(Be—P) = 198,2 qm und d(Be—As) = 206,0 pm. IR-Spektren belegen die Existenz von [Sb—Be—Sb]4--Anionen auch in K4BeSb2, welches im hexagonalen System mit Z = 2 kristallisiert. Die Schwingungsspektren der Verbindungen wurden gemessen. Die Zuordnung der beobachteten Frequenzen basiert auf der D∞h-Symmetrie einer isolierten [X—Be—X]4--Einheit.
    Additional Material: 3 Ill.
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  • 4
    ISSN: 0044-2313
    Keywords: Antimonide triantimonidometallates(III) ; preparation ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Antimonide Triantimonidometallates(III) Cs6K3Sb[AlSb3] and Cs6K3Sb[GaSb3]The novel compounds Cs6K3Sb[AlSb3] and Cs6K3Sb[GaSb3] are formed from stoichiometric mixtures of Cs, AlSb (GaSb) and KSb in sealed niobium ampoules at 950 K. The hexagonal structures are especially characterized by one-dimensional rod packings 1∞[Cs6K3Sb] which are formed from columns of condensed (Cs6K6/2) icosahedra. The icosahedra are centered by Sb3-- anions. The trigonal planar anions [AlSb3]6-- and [GaSb3]6-- are embedded between the icosahedra columns, and they are coordinated by alkali metal atoms. The FIR spectra were assigned to the vibrations of the [MSb3]6-- anions, with respect to the 6m2-D3h symmetry.(P63/mmc, No. 194; a = 1101.7 and 1097.2 pm; c = 1158.9 and 1150.1 pm; Z = 2; Single crystal data: 574 and 546 reflections; R = 0.073 and 0.029. Distances:d(Al—Sb) = 265.4 pm; d(Ga—Sb) = 265.1 pm; d(Sb—Cs) = 401.6-423.0 pm; d(Sb—K) = 358.6-367.3 pm).
    Notes: Die neuen Verbindungen Cs6K3Sb[AlSb3] und Cs6K3Sb[GaSb3] entstehen aus stöchiometrischen Gemischen von Cs, AlSb (GaSb) und KSb in verschweißten Niob-Ampullen bei 950 K. Besonderes Merkmal der hexagonalen Strukturen sind eindimensionale Stabpackungen 1∞[Cs6K3Sb], gebildet aus Säulen kondensierter (Cs6K6/2)-Ikosaeder. Die Ikosaeder sind von Sb3---Anionen zentriert. Zwischen den Ikosaedersäulen sind die trigonal-planaren Anionen [AlSb3]6-- bzw. [GaSb3]6-- eingebettet. Sie werden durch die Alkalimetallatome koordiniert. Die FIR-Spektren können den Schwingungen der Anionen [MSb3]6-- mit der Symmetrie 6m2-D3h zugeordnet werden.(P63/mmc, Nr. 194; a = 1101,7 bzw. 1097,2 pm; c = 1158,9 bzw. 1150,1 pm; Z = 2; Einkristalldaten: 574 bzw. 546 Reflexe; R = 0,073 bzw. 0,029. Abstände: d(Al—Sb) = 265,4 pm; d(Ga—Sb) = 265,1 pm; d(Sb—Cs) = 401,6-423,0 pm; d(Sb—K) = 358,6-367,3 pm).
    Additional Material: 3 Ill.
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  • 5
    ISSN: 0044-2313
    Keywords: Alkali metal pnictido indates, -gallates ; crystal structures ; vibrational spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: K2NaGaP2, Cs2NaGaP2, K2NaGaAs2, K2NaInP2 and K2NaInAs2, Compounds with the Polyanions 1∞[MX4/2]3- (M=Ga, In; X=P, As) isosteric with SiS2The title compounds are synthesized from stoichiometric mixtures of the elements or from Na, KP(KAs), Cs4P6 and MX (M=Ga, In; X=P, As) at 950K. They are isotypic and crystallize in the space group Ibam (No. 72) with Z=4. The anionic partial structure is characterized by infinite chains 1∞[MX4/2]3- which are isosteric to SiS2. Vibrational spectra are measured and interpreted based on the symmetry D4h-P(2/m 2/c)42/m of the isolated polymer chain 1∞[MX2]3-. A good agreement between observed and calculated frequencies is obtained by using a force field of the tetrameric fragment [M4X10]18- (three four-membered M2X2 rings).
    Notes: Die Titelverbindungen werden aus den stöchiometrischen Gemischen der Elemente oder aber aus Na, KP(KAs) bzw. Cs4P6 und MX (M = Ga, In; X = P, As) bei 950 K dargestellt. Sie sind isotyp und kristallisieren in der Raumgruppe Ibam (Nr. 72) mit Z=4. Die anionische Partialstruktur ist durch unendliche Ketten 1∞[MX4/2]3- charakterisiert, isoster zu SiS2. Schwingungsspektren wurden gemessen und mit der Symmetrie D4h-P(2/m 2/c)42/m der isolierten Polymerkette 1∞[MX2]3- interpretiert. Eine gute Übereinstimmung zwischen den beobachteten und berechneten Frequenzen erhält man bei Verwendung des Kraftfeldes für das tetramere Fragment [M4X10]18- (drei M2X2-Vierringe).
    Additional Material: 5 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 129 (1996), S. 1015-1023 
    ISSN: 0009-2940
    Keywords: Ba14InP11 ; Zintl phase ; Tetraphosphidoindate(III) anions ; Asymmetric [P3]7- polyanions ; Interpenetrating hierarchical frameworks ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ba14InP11 was prepared from the elements in a sealed stainless steel ampoule at 1345 K. The compound is black, brittle and very sensitive to air and moisture. Ba14InP11 crystallises in the tetragonal Ca14AlSb11 type (space group I41/acd, No. 142; a = 17.097 (2) Å, c, = 8, Pearson code tI208). The structure contains isolated P3-, linear [P3]7- and tetrahedral [InP4]9- anions. The X-ray structure analysis and the vibrational spectra show that the [P3]7- polyanion is strongly asymmetric with d(P-P) = 2.28 Å and 4.10 Å, corresponding to a [P2]4- dumbbell weakly coupled to a single p3- anion. The tetraphosphidoindate(III) anion [InP4]9- is slightly compressed along the 4 axis, with bond lenght d(In-P) = 2.71 Å. It is shown that the structure is hierarchically related to that of Cu2O, with two interpenetrating frameworks, in which the O and Cu atoms are replaced by condensed [InP4/2] tetrahedron and [BaP4P2/2] octahedra, respectively. Both frameworks are meso configured, containing alternate R and S fragments. The other Ba cations envelop the P6 octahedra and P3 triads forming condensed cubes, tetragonal antiprisms and bicapped trigonal prisms. Therefore, the structure also forms a heterogeneous framework of centred PBa8/2tap tetragonal antiprisms and BaBa8/2cub cubes, consisting of two interpenetrating enantiomorphic nets (R and S) similar to those in the cubic phase RhBi4.
    Additional Material: 8 Ill.
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  • 7
    ISSN: 0044-8249
    Keywords: 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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  • 8
    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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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 104 (1992), S. 936-939 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0044-2313
    Keywords: Ba3Ge4C2 ; Zintl Phase ; tetrahedro-Tetragermanide [Ge4]4- Anions ; Acetylenide [C2]2- Anions ; Vibrational Spectra ; Force Constants ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tribarium tetrahedro-Tetragermanid- Acetylenid, Ba3[Ge4][C2] - Synthese, Struktur und EigenschaftenBa3Ge4C2 bildet sich aus den Elementen order durch die Umsetzung von BaC2 mit BaGe2 bei 1530 K (korundtiegel in geschlossener Stahlampulle). Die Verbindung ist ein Halbleiter (grau; Eg = 1.1 eV), spröde, und sehr feuchtigkeitsempfindlich. Sie reagiert mit NH4Cl bei ca. 400 K unter Bildung von Acetylen und Germanen bis Ge4Hn. Der neue Ba3Ge4C2-Strukturtyp (Raumgruppe I4/mcm, No. 140; a = 8.840(1) Å, c = 12.466(1) Å; Z = 4, Pearsonsymbol tI36) enthält zwei isolierte Polyanionen, nämlich Tetrahedro-tetragermanid [Ge4]4- und Acetylenid [C2]2-. Die Bindungslängen betragen d(Ge—Ge) = 2.517 Å (4×) bzw. 2.641 Å (2x) und d(C≡C) = 1.20 Å. Die Struktur von Ba3[Ge4][C2] ist durch Atom/Cluster-Substitutionen ([Ge4] statt Ca; [C2] statt Ti; Ba statt O) eine hierarchische Variante der Perowskit-Struktur CaTiO3. Das Raman-Spektrum zeigt Banden bei 168, 199 und 280 cm-1 bzw. 1796 cm-1, die für die Polyanionen [Ge4]4- und [C2]2- charakteristisch sind.
    Notes: Ba3Ge4C2 is formed at 1530 K from the elements or by reaction of BaC2 with BaGe2 (corundum crucible; steel ampoule). The compound is a semiconductor (grey colour; Eg = 1.1 eV), brittle, very sensitive to moisture, and reacts with NH4Cl at about 400 K forming acetylene and germanes up to Ge4Hn. The new Ba3Ge4C2 structure type (space group I4/mcm, No. 140; a = 8.840(1) Å, c = 12.466(1) Å; Z = 4, Pearson code tI36), contains two kinds of isolated polyanions, namely tetrahedro-tetragermanide [Ge4]4- and acetylenide [C2]2- anions. The bond lengths are d(Ge-Ge) = 2.517 Å (4×) and 2.641 Å (2×), and d(C≡C) = 1.20 Å. The Ba3[Ge4][C2] structure is a hierarchical derivative of the perovskite (CaTiO3) generated by a partial atom/cluster replacement ([Ge4] for Ca, [C2] for Ti and Ba for O). The Raman spectrum shows bands at 168, 199 and 280 cm-1, and at 1796cm-1 characteristic for [Ge4]4- and [C2]2- polyanions, respectively.
    Additional Material: 5 Ill.
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