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11.
Crystal growth from anhydrous hydrogen fluoride solutions of M2+ (M=Cu, Ag) and [AuF6]− gave M(AuF6)2 salts (M=Cu, Ag). Similar attempts to prepare single crystals of the corresponding nickel, zinc and magnesium salts failed. The crystal structure of Cu(AuF6)2 consists of layers of Cu2+ cations connected by [AuF6]− anions, thus forming slabs. Only van der Waals interactions exist between adjacent slabs. The crystal structure of Ag(AuF6)2 consists of a three-dimensional framework in which Ag+ cations are linked by [AuF6]− anions. Both structures are members of the MII(XVF6)2 family, in which seven different structure types have been observed to date. In the crystal structure of O2(CuF)3(AuF6)4 ⋅ HF, the bridging AuF6 units connect [−Cu−F−Cu−F−]∞ chains to form stacks between which O2+ cations and HF molecules are located. 相似文献
12.
Integrated Transmission Electron and Single‐Molecule Fluorescence Microscopy Correlates Reactivity with Ultrastructure in a Single Catalyst Particle 下载免费PDF全文
Frank C. Hendriks Sajjad Mohammadian Dr. Zoran Ristanović Dr. Sam Kalirai Dr. Florian Meirer Prof. Dr. Eelco T. C. Vogt Dr. Pieter C. A. Bruijnincx Prof. Dr. Hans C. Gerritsen Prof. Dr. Bert M. Weckhuysen 《Angewandte Chemie (International ed. in English)》2018,57(1):257-261
Establishing structure–activity relationships in complex, hierarchically structured nanomaterials, such as fluid catalytic cracking (FCC) catalysts, requires characterization with complementary, correlated analysis techniques. An integrated setup has been developed to perform transmission electron microscopy (TEM) and single‐molecule fluorescence (SMF) microscopy on such nanostructured samples. Correlated structure–reactivity information was obtained for 100 nm thin, microtomed sections of a single FCC catalyst particle using this novel SMF‐TEM high‐resolution combination. High reactivity in a thiophene oligomerization probe reaction correlated well with TEM‐derived zeolite locations, while matrix components, such as clay and amorphous binder material, were found not to display activity. Differences in fluorescence intensity were also observed within and between distinct zeolite aggregate domains, indicating that not all zeolite domains are equally active. 相似文献
13.
Back Cover: Integrated Transmission Electron and Single‐Molecule Fluorescence Microscopy Correlates Reactivity with Ultrastructure in a Single Catalyst Particle (Angew. Chem. Int. Ed. 1/2018) 下载免费PDF全文
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Zeolite-based monoliths (Cu/ZSM-5 on cordierite) are prepared and used to catalyze direct decomposition of nitrogen monoxide. Two-dimensional heterogeneous model is applied to describe the behavior of the monolith reactor, with the emphasis on the features introduced due to coupling of flow, mass transfer and chemical reaction. The proposed model has been verified by comparing computer simulation data with laboratory experimental data. It is shown that both inter- and intraphase diffusion limitations have to be considered when modeling complex reactor configuration, such as monolith reactors, especially when monolith with thicker catalytic layer are used at higher temperatures. 相似文献
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17.
Davor Margetić Ronlad N. Warrener Mirjana Eckert-Maksić Ivana Antol Zoran Glasovac 《Theoretical chemistry accounts》2003,109(4):182-189
DFT calculations of 7′–oxasesquinorbornenes and 7,7′-dioxasesquinorbornenes using the B3LYP/6–31G* method are reported.
All the investigated structures (syn- and anti- derivatives) showed significant non-planarity of the central double bond, with the exception of those anti-derivatives possessing symmetrical structures. The influence of the replacement of the methylene groups at position 7- of
the norbornene fragment with oxygen and the introduction of second and third (peripheral) double bonds and benzene rings on
the molecular and electronic structures of these molecules have also been investigated.
Received: 11 November 2002 / Accepted: 6 June 2002 /
Published online: 29 April 2003 相似文献
18.
eljko K. Jaimovi Zoran D. Tomi Gerald Giester Vukadin M. Leovac 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):m381-m383
In the crystal structure of the title complex, [Co(C6H8N3S)3], the CoIII atom is octahedrally coordinated by three monodeprotonated bidentate 3,5‐dimethyl‐1H‐pyrazole‐1‐thiocarboxamide ligands with two thiocarboxamide N atoms in axial positions. The asymmetric unit contains two molecules (A and B) and these molecules are arranged in chains in an alternating fashion connected by N—H⋯S interactions. 相似文献
19.
The reaction between AgBF4 and excess of SbF5 in anhydrous hydrogen fluoride (aHF) yields the white solid AgSb2F11 after the solvent and the excess of SbF5 have been pumped off. Reaction between equimolar amounts of AgSb2F11 and AgBF4 yields AgSbF6. Meanwhile, oxidation of solvolyzed AgSb2F11 in aHF by elemental fluorine yields a clear blue solution of solvated Ag(II) cations and SbF6- anions. AgSb2F11 is orthorhombic, at 250 K, Pbca, with a=1091.80(7) pm, b=1246.28(8) pm, c=3880.2(3) pm, V=5.2797(6) nm3, and Z=24. The crystal structure of AgSb2F11 is related to the already known crystal structure of H3OSb2F11. Vibrational spectra of AgSb2F11 entirely match the literature-reported vibrational spectra of beta-Ag(SbF6)2, for which a formulation of a mixed-valence AgI/AgIII compound was suggested (AgIAgIII(SbF6)4). On the basis of obtained results it can be concluded that previously reported beta-Ag(SbF6)2 is in fact Ag(I) compound with composition AgSb2F11. 相似文献
20.
Zoran S. Marković Jasmina M. Dimitrić Marković Ćemal B. Doličanin 《Theoretical chemistry accounts》2010,127(1-2):69-80
The extensive theoretical study of the interaction of one of the most abundant and reactive flavonols, quercetin, with hydroperoxy radical (HOO·), using the M052X/6-31 + Gd, p level of theory, was performed. Results indicating that quercetin is not a planar molecule are in accord with the X-ray analysis. The applied method successfully reproduces the bond dissociation enthalpy, and reveals that the reaction of quercetin with the hydroperoxy radical is governed by a hydrogen atom transfer mechanism. It is confirmed that the 3′OH and 4′OH are the most reactive sites, and that the reaction in the 3′OH position is faster than that in the 4′OH position. 相似文献