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991.
Investigations into Tin(IV) Alkoxides. II. Isolation and Characterization of the Compound Sn3O(OiBu)1010 · 2i-BuOH. The First Example of a Partially Hydrolized Tin(IV) Alkoxide The partial hydrolysis product Sn3O(OiBu)10 · 2i-BuOH was obtained by slow hydrolysis of the reaction product of tin tetrachloride with sodium isobutoxide. The compound forms colourless, moisture sensitive crystals, which easily release the coordinated solvent molecules in dry air. Its crystal and molecular structure has been determinated by single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P1 with a = 1363.5(7), b = 1462.7(10), c = 1637.7(7) pm, α = 95.40(5)°, β = 96.79(4)°, γ = 102.12(5)° and Z = 2. The crystal structure consists of discrete, trimeric molecules with octahedrally coordinated tin atoms which are connected to each other corresponding to the formulation Sn3(μ3-O)(μ2-OiBu)3(O1Bu)7 · (i-BuOH)2 by three isobutoxide groups bridging two metal atoms and a single threefold bridging oxygen atom 相似文献
992.
New Oxonium Bromochalcogenates(IV) — Synthesis, Structure, and Properties of [H3O][TeBr5] · 3 C4H8O2 and [H3O]2[SeBr6] Dark red crystals of the composition [H3O][TeBr5] · 3 C4H8O2 ( 1 ) were isolated from a saturated solution of TeBr4 in 1,4-dioxane containing a small amount of water. In this compound (space group P21/m, a = 8.922(4) Å, b = 13.204(7) Å, c = 9.853(5) Å, β = 91.82(4)° at 150 K) a square pyramidal [TeBr5]? anion has been isolated for the first time. The coordination sphere of the anion is completed to a distorted octahedron by weak interaction with a dioxane molecule of the cationic system. The [H3O]+ cations are connected to chains by dioxane molecules. At room temperature the compound is stable only in its mother liquor. Crystalline [H3O]2[SeBr6] ( 2 ) (space group Fm3m, a = 10.421(1) Å at 170 K) is a bromoselenous acid of high symmetry. The [H3O]+ ion is only weakly coordinated by Br atoms of the anion. The anions are isolated octahedral [SeBr6]2? units. The structure is isotypic to the K2[PtCl6] structure. Despite being a halogenochalcogen(IV) acid, 2 exhibits a remarkable thermal stability. Both oxonium compounds were characterized by single-crystal X-ray structure analyses. Vibrational spectra of 2 are reported. 相似文献
993.
1INTRODUCTIONRecently,considerableattentionhasbeenpaidtotheinvestigationofcoordinationchemistryofmanganeseindifferentoxidationstatesnotonlybecauseofthediscoveryoftightlyboundmanganeseatomsinvariousbiomolecules[libutalsobecauseoftheirinterestingstructural,magneticandspectroscopicfeatures.Wehavepreparedseveralcomplexesofmanganese(n)withdifferentligands.Thestructuresandfeaturesofthesecompoundsarestudiedsystematically.Inthispaperwedescribethestructureofthecomplexwiththeligandsofphenanthroline… 相似文献
994.
稀土高氯酸盐开环冠醚三缩乙二醇(EO_3)[La(C_6H_(14)O_4)_3(H_2O)](ClO_4)_3·H_2O,单斜晶系,P2_1/c空间群。晶胞参数为:a=15.474(2),b=11.386(1),c=20.841(4),β=99.82(1)°,V=3618(1),MoKα,Z=4,D_c=1.718g/cm3,μ=1.499mm ̄(-1)。全矩阵最小二乘精细修正,结构因子R=0.056,R_w=0.083。中心原子La与开环冠醚醚链上的O(1)~O(9)及一个水分子形成10配位双帽四方反棱柱结构。弱配体高氯酸根不参加配位。 相似文献
995.
B. V. Bukvetskii E. V. Fedorenko A. G. Mirochnik V. E. Karasev 《Journal of Structural Chemistry》2007,48(6):1148-1151
The crystal structure of boron difluoride 3-phenylthiopentane-2,4-dionate was determined. The relationship between the structure and luminescent properties is traced in the series of boron difluoride acetyl acetonates (acetyl acetonate, phenylacetyl acetonate, and phenylthioacetyl acetonate). The presence of the π stacking interactions in boron difluoride phenylthioacetyl acetonate crystals leads to increased intensity and bathochromic shift of the fluorescence band. 相似文献
996.
A sample pretreatment technique for silicon nitride involving digestion and matrix/traces separation was developed by means of radiotracers and applied to analysis of this material by inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry and graphite furnace atomic absorption spectrometry. The results obtained for a high purity silicon nitride material by these methods are compared each with the other and with those obtained by neutron activation analysis. The limits of detection and the capabilities of the methods are compared and discussed. 相似文献
997.
0IntroductionRecently,thecompoundscontaining1H-1,2,4-tr-iazolegrouphaveattractedmuchinterestbecauseoftheirexhibitingsomefungicidalactivityandplantgrowthregulatingactivity犤1犦,andshowingantibacterialactivityagainstPucciniareconditeandrootsgrowthregulationforcucumber犤2犦.Also,suchcompoundsareincreasinglybeingstudiedbecauseofthecoordinationchemistryofazolesactingasligandsintransitionmetalcompounds.Asamatteroffact,thetriazolederivativeshavebeenextensivelyusedasterminalandbridgingligands,andthey… 相似文献
998.
Olga N. Kataeva Aidar T. Gubaidullin Igor A. Litvinov Olga A. Lodochnikova Lenar R. Islamov Alexander I. Movchan Galina A. Chmutova 《Journal of Molecular Structure》2002,610(1-3):175-179
Crystal and molecular structure of 1-phenyl-3-benzoylamino-4-benzoylpyrazol-2-in-5-one as a product of the benzoylation of 1-phenyl-3-benzoylaminopyrazol-2-in-5-one was characterised by X-ray single crystal diffraction. It is shown that 1-phenyl-3-benzoylamino-4-benzoylpyrazol-2-in-5-one exists in the solid phase in an NH-tautomeric form, which is stabilised by two intramolecular hydrogen bonds and one intermolecular bond with the solvate dioxane molecule, the latter being used as a solvent for recrystallisation. 相似文献
999.
Safoklov B. B. Atovmyan E. G. Nikonova L. A. Tkachev V. V. Aldoshin S. M. 《Russian Chemical Bulletin》2002,51(12):2224-2229
Pyrrole-2-carbaldehyde isonicotinoylhydrazone (1) and its hydrate [1·H2O] (2) were studied by single-crystal X-ray diffraction analysis. The introduction of the pyrrole substituent into N"-substituted isonicotinic hydrazide (INH) causes the intramolecular redistribution of the electron density compared to those in INHs studied earlier, which increases the basicity of the hydrazone nitrogen atom (N") involved in intermolecular hydrogen bonding. This effect has not been observed in the structures of N"-substituted INHs and benzhydrazides studied previously. Intermolecular hydrogen bonds play a decisive role in the formation of the crystal structures of 1 and 2. 相似文献
1000.
Alicia Reyes-Arellano Roland Boese Ingo Steller Reiner Sustmann 《Structural chemistry》1995,6(6):391-396
The crystal structures of molecular complexes betweenmeso- 1,2-diphenyl-1,2-ethanediol and two bisimines (N,N-(dibenzylidene)-ethylenediamine and glyoxylidene-bis(2,4-dimethyl-3-pentyl-amine) are reported at different temperatures. The structure-determining motif of the cocrystalline arrangement is one single O-H . N hydrogen bond resulting in infinite ladderlike polymers. The supramolecular structure is formed by recognition of fitting species: Thed- orl-isomers do not arrange in such structures.1H NMR experiments show that no prearrangements take place by forming complexes in solution. 相似文献