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  • 1
    Electronic Resource
    Electronic Resource
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 53 (1997), S. 337-345 
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Synthetic tetrahedrite, Cu12Sb4S13, obtained by reaction of the elements, has been investigated at various temperatures in the 295–573 K range. It crystallizes in the cubic system with a = 10.3293 (6) Å, V = 1102.1 (2) Å3, space group I\overline 43m and Z = 2 at room temperature. The structure refinement converged to a residue of R = 0.0165 (at room temperature, wR = 0.0200) for 389 independent reflections and 34 refined parameters. A Gram–Charlier non-harmonic development of the atomic displacement factor for both independent Cu atoms was used. The results show a disorder for the three-coordinated Cu atom, within and perpendicular to the plane of the three surrounding S atoms. However, although the non-harmonic probability density deformation increases with raising the temperature within this plane, it barely changes in the perpendicular direction. This suggests two different types of disorder: static in-plane and dynamic out-of-plane, therefore underlining a possible diffusion pathway for copper ions. To check the significance of the observed effects, the errors for the one-particle potentials and the probability density function maps were calculated by means of a Monte-Carlo method.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0044-2313
    Keywords: P4Si ring systems ; NMR data, crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of the Silatetraphospholanes (tBuP)4SiMe2, (tBuP)4SiCl2, and (tBuP)4Si(Cl)SiCl3 Molecular and Crystal Structure of (tBuP)4SiCl2The reaction of the diphosphide K2[(tBuP)4] 7 with the halogenosilanes Me2SiCl2, SiCl4 or Si2Cl6 in a molar ratio of 1:1 leads via a [4 + 1]-cyclocondensation reaction to the silatetraphospholanes (tBuP)4SiMe2 1,1-dimethyl-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholane, 1, (tBuP)4SiCl2, 1,1-dichloro-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholane, 2, and (tBuP)4Si(Cl)SiCl3, 1-chloro-1-trichlorsilyl-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholane, 3, respectively, with the 5-membered P4Si ring system. The reaction leading to 1 is accompanied with the formation of the by-product Me2(Cl)-Si-(tBuP)4-Si(Cl)Me2 1a (5:1), which has a chain structure. On warming to 100°C 1a decomposes to 1 and Me2SiCl2. The compounds 2 and 3 do not react further with an excess of 7 due to strong steric shielding of the ring Si atoms by the t-butyl groups. 1, 2 and 3 could be obtained in a pure form and characterized NMR spectroscopically; 2 was also characterized by a single crystal structure analysis. 1a was identified by NMR spectroscopy only.
    Notes: Bei der Reaktion zwischen dem Diphosphid K2[(tBuP)4] 7 und den Halogensilanen Me2SiCl2, SiCl4 bzw. Si2Cl6 im Molverhältnis 1:1 findet eine [4 + 1]-Cyclokondensationsreaktion statt, bei der die Silatetraphospholane (tBuP)4SiMe2, 1,1-Dimethyl-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholan, 1, (tBuP)4SiCl2, 1,1-Dichloro-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholan, 2, und (tBuP)4Si(Cl)SiCl3, 1-Chloro-1-trichlorsilyl-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholan, 3, mit dem binären P4Si-Fünfringgerüst gebildet werden. Bei der Synthese von 1 entsteht ferner das kettenförmige Nebenprodukt Me2(Cl)Si-(tBuP)4-Si(Cl)Me2 1a (5:1), das beim Erwärmen auf 100°C unter Bildung von 1 und Me2SiCl2 zerfällt. Die Verbindungen 2 und 3 reagieren nicht mit überschüssigem 7, was auf eine starke sterische Abschirmung der Ring-Si-Atome durch die benachbarten t-Butyl-Gruppen zurückzuführen ist. 1, 2 und 3 konnten in reiner Form isoliert und NMR-spektroskopisch charakterisiert werden; 1a konnte nur 31P-NMR-spektroskopisch identifiziert werden. Von 2 wurde eine Einkristallstrukturanalyse durchgeführt.
    Additional Material: 1 Ill.
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  • 3
    ISSN: 0044-2313
    Keywords: [Disodium(2 +)][1,2-Diselena-diboranate(2 -)] ; [Tetraphenylphosphonium(1 +)][μ2-Selena-(diboranyl)boranate(1 -)] ; preparation ; SCF calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Vibrational Spectroscopic Investigation of [H3B—Se—Se—BH3]2- and [H3B-μ2-Se(B2H5)]- Crystal Structure and Theoretical Investigation of the Molecular Structure of [H3B-μ2-Se(B2H5)]-M2[H3B—Se—Se—BH3] 1 is produced by the reaction between elemental selenium and MBH4 (1 : 1) in triglyme (diglyme), under dehydrogenation. 1 reacts with an excess of B2H6 to give M[H3B-μ2-Se(B2H5)] 2 which is also formed in the reaction of THF · BH3 with 1. These reactions proceed under cleavage of the Se—Se bond and hydrogen evolution. [(C6H5)4]Br reacts with Na · 2 to form [(C6H5)4P] · 2 which crystallizes in the tetragonal space group I4 (Nr. 82). An X-ray structure determination failed because of disordering of the cation and anion. 11B, 77Se NMR shifts and 1J(11B1H) coupling constants as well as IR- and Raman spectroscopic investigations convey further structural information. Structural data of 2 have been calculated by SCF methods. The anion of 2 may be viewed either as an adduct of Se with B3H8-, or as a bridge substituted selena derivative of B2H6.
    Notes: Bei der Reaktion zwischen elementarem Selen und MBH4 (1 : 1) (M = Na, Li) in Triglyme (Diglyme) entsteht unter Wasserstoffabspaltung M2[H3B—Se—Se—BH3] 1. Bei der Behandlung von 1 mit überschüssigem B2H6 oder THF · BH3 wird die Se—Se-Bindung gespalten und es entsteht unter erneuter Wasserstoffabspaltung M[H3B-μ2-Se(B2H5)] 2. Aus Na · 2 und [(C6H5)4P]Br entsteht [(C6H5)4P] · 2, welches tetragonal in der Raumgruppe I4 (Nr. 82) kristallisiert. Kation und Anion sind im Kristall fehlgeordnet. Strukturinformationen konnten aus den 11B-, 77Se- und 1J(11B1H)-Daten einerseits und den IR- und Raman-spektroskopischen Untersuchungen andererseits erhalten werden. Aus SCF-Rechnungen erhielten wir die Strukturparameter für das Anion 2. 2 kann sowohl als Addukt von Se an B3H8- als auch als brückensubstituiertes Selena-Derivat des B2H6 aufgefaßt werden.
    Additional Material: 3 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 969-974 
    ISSN: 0044-2313
    Keywords: Copper(I) selenium tellurium halides ; chalcogen ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: CuSeTeCl, CuSeTeBr, and CuSeTeI: Compounds with ordered ∞1[SeTe] ScrewsThe hitherto unknown copper(I) chalcogen halides CuSeTeCl, CuSeTeBr and CuSeTeI have been prepared and their crystal structures were determined. The compounds of general composition CuSeTeX crystallize in the monoclinic system, space group P21/n (No. 14), Z = 4, a = 7.9796(9), b = 4.7645(8), c = 10.843(3) Å, β = 104.12(1)°, V = 399.8(1) Å3 (X = Cl), a = 8.155(3), b = 4.765(2), c = 11.286(4) Å, β = 104.21(3)°, V = 425.1(3) Å3 (X = Br) and a = 8.4370(9) b = 4.7652(5), c = 11.996(2) Å, β = 103.178(9)°, V = 469.6(1) Å3 (X = I). The crystal structures show infinite onedimensional screws YY′ of chalcogen atoms, with Y = Se and Y′ = Te alternately. The coordinations of Se and Te in these compounds are quite different.
    Notes: Die bisher unbekannten Kupfer(I)-chalkogenhalogenide CuSeTeCl, CuSeTeBr und CuSeTeI wurden erstmals erhalten und ihre Kristallstrukturen bestimmt. Sie kristallisieren monoklin, RG P21/n (Nr. 14), Z = 4, mit a = 7,9796(9), b = 4,7645(8) und c = 10,843(3) Å, β = 104,12(1)°, V = 399,8(1) Å3 (X = Cl), a = 8,155(3), b = 4,765(2) und c = 11,286(4) Å, β = 104,21(3)°, V = 425,1(3) Å3 (X = Br) sowie a = 8,4370(9), b = 4,7652(5) und c = 11,996(2) Å, β = 103,178(9)°, V = 469,6(1) Å3 (X = I). In den Kristallstrukturen liegen eindimensional unendliche Schrauben YY′ vor, mit alternierend Y = Se und Y′ = Te. Die Umgebungen von Se und Te sind deutlich verschieden.
    Additional Material: 3 Ill.
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  • 5
    ISSN: 0044-2313
    Keywords: Phosphanediyl ; Halogenocyclotetraphosphanes ; NMR Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: In situ Generation of [PX] and Insertion into (tBuP)3, (X = Cl, Br). Synthesis of the Functionalized Cyclophosphanes (tBuP)3PX, [1-(tBu)(X)P-2,3,4-(tBu)3]P4 and Structure Analysis of (tBuP)3PClThe redox system PX3/SnX2 (X = Cl, Br) can be used as a source for the in situ generation of halogenphosphanediyl [PX]. In the presence of tri-t-butylcyclotriphosphane (tBuP)3 the intermediately formed [PX] is added to a ring P atom followed by an insertion reaction, which leads to a ring expansion, whereby monohalogenocyclotetraphosphanes (tBuP)3PX (X = Cl, Br; 1, 2) are formed. Excess [PX] does not lead to further ring expansion but through a complex reaction course to the functionalized cyclotetraphosphanes [1-(tBu)(X)P-2,3,4-(tBu)3]P4, 3 (X = Br); 7 (X = Cl). 1, 2 and 3 could be obtained in a pure form and NMR and mass spectroscopically, 7 31P-NMR spectroscopically, characterized. For 1 and 7 31P—35,37Cl-isotopic shifts could be identified. 1 was further characterized by an X-ray structure analysis.
    Notes: Das Redoxsystem PX3/SnX2 (X = Cl, Br) kann als Quelle zur in situ-Bildung von Halogenphosphandiyl [PX] verwendet werden. In Gegenwart von Tri-t-butylcyclotriphosphan (tBuP)3 wird intermediär auftretendes [PX] zuerst an ein Ring-P-Atom addiert, dann unter Ringexpansion insertiert, wobei Monohalogenocyclotetraphosphane (tBuP)3PX (X = Cl, Br; 1, 2) gebildet werden. Überschüssiges [PX] führt nicht zu einer weiteren Ringexpansion; vielmehr entstehen in einem komplexen Reaktionsverlauf die funktionalisierten Cyclotetraphosphane [1-(tBu)(X)P-2,3,4-(tBu)3]P4, 3 (X = Br); 7 (X = Cl). 1, 2 und 3 konnten in reiner Form isoliert und NMR- sowie massenspektroskopisch, 7 31P-NMR-spektroskopisch, charakterisiert werden. Bei 1 und 7 konnten 31P—35,37Cl-Isotopieverschiebungen nachgewiesen werden. Von 1 wurde eine Röntgenstrukturanalyse durchgeführt.
    Additional Material: 1 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 853-857 
    ISSN: 0044-2313
    Keywords: Copper(I) sulfur tellurium halides ; chalcogen ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: CuClS0.94Te1.06 and CuBrS0.92Te1.08, Two New Copper(I) Chalcogen Halides Containing Neutral ∞1[STe] ScrewsCuClS0.94Te1.06 and CuBrS0.92Te1.08 are two new, isotypic compounds of general composition CuXYY′ (X = halide, Y, Y′ = chalcogen) with a mixed chalcogen substructure. They crystallize in the monoclinic system, space group P21/n (No. 14), a = 7.878(2), b = 4.727(1), c = 10.759(2) Å, β = 103.97(2)°, V = 388.8(2) Å3 (CuClS0.94Te1.06) and a = 8.043(3), b = 4.746(2), c = 11.240(4) Å, β = 103.46(3)°, V = 417.3(3) Å3 (CuBrS0.92Te1.08), both with Z = 4. The crystal structures are dominated by ordered ∞1[STe±0]-screws. From a crystal chemical point of view the sulfur and tellurium atoms are significantly different. The melting points are 341 °C (CuClS0.94Te1.06) and 336 °C (CuBrS0.92Te1.08). The compounds CuXYY′ (X = Cl, Br, I; Y, Y′ = S, Se, Te) are compared and discussed.
    Notes: Mit CuClS0.94Te1.06 und CuBrS0.92Te1.08 wurden zwei neue, isotype Verbindungen der Zusammensetzung CuXYY′ (X = Halogenid, Y, Y′ = Chalkogen) mit gemischtem Chalkogenteilgitter erhalten. Sie kristallisieren monoklin, RG P21/n (Nr. 14) mit a = 7,878(2), b = 4,727(1) und c = 10,759(2) Å, β = 103,97(2)°, V = 388,8(2) Å3 (CuClS0.94Te1.06) bzw. a = 8,043(3), b = 4,746(2) und c = 11,240(4) Å, β = 103,46(3)°, V = 417,3(3) Å3 (CuBrS0.92Te1.08), jeweils mit Z = 4. Strukturbestimmendes Merkmal sind die geordneten ∞1[STe±0]-Schrauben. Kristallchemisch sind die Schwefel- und Telluratome deutlich unterschiedlich. Die Schmelzpunkte liegen bei 341 °C (CuClS0.94Te1.06) bzw. 336 °C (CuBrS0.92Te1.08). Die Strukturen von CuXYY′ (X = Cl, Br, I; Y, Y′ = S, Se, Te) werden verglichen und diskutiert.
    Additional Material: 2 Ill.
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  • 7
    ISSN: 0044-2313
    Keywords: Thia- and selena-arachno-undecaborane ; preparation ; spectroscopy ; ab initio/IGLO ; GIAO/NMR method ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thia- and Selena-arachno-undecaborane 6,7-μ-(CH3E)B10H13. Crystal Structure of arachno-6,7-μ-(CH3Se)B10H13. Theoretical Investigations of the Molecular Structures and 11B NMR Shifts of arachno-6,7-μ-(CH3E)B10H13The reaction of B10H14 with (CH3)2S yields with loss of H2 the base adduct 6,9-[(CH3)2S]2B10H12. Although an analogous reaction between B10H14 with disulfanes or diselenanes was expected to produce 6,9 bridged dichalcogen derivatives, (CH3)2S2 failed to react even under reflux conditions. Trisulfane (CH3)2S3 does react, but the pathway is different and leads to (CH3S)B10H13 2 without loss of H2. Unlike of (CH3)2S2, (CH3)2Se2 yields (CH3Se)B10H13, 3. Both 2 and 3 are formed by substitution of a bridging hydrogen and could be obtained in pure form and characterized 11B NMR spectroscopically. A single crystal X-ray structure analysis also was performed on 3 (space group P21/c). The molecular structures of 2 and 3 were optimized at the MP2 level and 11B NMR shifts were computed at the IGLO-SCF, GIAO-SCF and GIAO-B3LYP levels of theory.
    Notes: Bei der Reaktion zwischen B10H14 und (CH3)2S erfolgt unter H2-Abspaltung eine zweifache Adduktbildung, die zu 6,9-[(CH3)2S]2B10H12 führt. Die analoge Umsetzung zwischen B10H14 mit Disulfanen bzw. Diselenanen führte jedoch nicht zu den 6,9-Dichalkogen-verbrückten Derivaten. Bei der Umsetzung mit (CH3)2S2 findet selbst unter Refluxbedingungen keine Reaktion statt, wohl aber mit dem Trisulfan (CH3)2S3. Die Reaktion verläuft aber nicht unter H2-Abspaltung. Vielmehr wird dabei ein Brücken-H-Atom durch eine CH3S-Gruppe substituiert unter Bildung von (CH3S)B10H13 2. Im Gegensatz zu (CH3)2S2 findet aber mit (CH3)2Se2 ebenfalls eine Brücken-H-Substitution statt, wobei (CH3Se)B10H13 3 gebildet wird. 2 und 3 konnten in reiner Form isoliert und 11B-NMR-spektroskopisch charakterisiert werden. Von 3 wurde eine Röntgenstrukturanalyse durchgeführt (Raumgruppe P21/c) und von 2 und 3 die Molekülstrukturen auf MP2-Niveau optimiert sowie 11B-NMR- Verschiebungen mit IGLO-SCF, GIAO-SCF und GIAO-B3LYP berechnet.
    Additional Material: 3 Ill.
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