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1.
H. Sofer O. E. Polansky G. Derflinger 《Monatshefte für Chemie / Chemical Monthly》1968,99(5):1879-1894
Zusammenfassung Die p-LokalisierungsenergieL
p nachBrown wird als Maß derDiels—Alder-Reaktivität in Beziehung gesetzt zu den Äthylen-, Butadien- und Benzol-Charakterordnungen . Bei Angriff an peripherencisoiden C4-Einheiten des Moleküls fälltL
p erwartungsgemäß mit
dienoid
und steigt mit den anderen Charakterordnungen. Werden innerhalb eines einzigen Benzolrings nur sekundäre C-Atome angegriffen, so steigtL
p mit allen Charakterordnungen, werden hingegen auch tertiäre C-Atome miterfaßt, fälltL
p mit allen Charakterordnungen. Dieser Hinweis auf wahrscheinliche Reaktionsmechanismen zeigt neuerlich die Signifikanz dieser Reaktionsindices.
Mit 4 Abbildungen
Als 1. Mitt. zählen wir die in zitierte Arbeit. 相似文献
Brown's p-localization energy as a measure for theDiels—Alder-reactivity is correlated to ethylene-, butadiene- and benzene-character orders. If the molecule is attacked at periphericcisoidic C4-units,L p decreases with dienoid and increases with the other 's, as expected. If in the reaction only secondary C-atoms of a single benzene ring are involved,L p increases with all character orders, but if tertiary C-atoms are also involved,L p decreases with the character orders. This hint of probable reaction mechanism shows once again the significance of these new indices of reactivity.
Mit 4 Abbildungen
Als 1. Mitt. zählen wir die in zitierte Arbeit. 相似文献
2.
3.
Zusammenfassung Unter Benützung der Gruppentheorie wird eine allgemeine Formel für dieHückel-Molekularorbitale der linearen Polyacene abgeleitet.
Mit 1 Abbildung 相似文献
By means of group theory a general formula for theHückel molecular orbitals of the linear polyacenes is derived.
Mit 1 Abbildung 相似文献
4.
Cyanide Bridged Platinum-Iron Complexes as Cisplatin Prodrug Systems: Design and Computational Study
Dr. Ariela W. Kaspi-Kaneti Srijana Bhandari Dr. Alexander Schubert Prof. Songping D. Huang Prof. Barry D. Dunietz 《Chemphyschem》2021,22(1):106-111
The potential role of cyanide-bridged platinum-iron complexes as an anti-cancer Pt(IV) prodrug is studied. We present design principles of a dual-function prodrug that can upon reduction dissociate and release concurrently six cisplatin units and a ferricyanide anion per prodrug unit. The prodrug molecule is a unique complex of hepta metal centers consisting of a ferricyanide core with six Pt(IV) centers each bonded to the Fe(III) core through a cyano ligand. The functionality of the prodrug is addressed through density functional theory (DFT) calculations. 相似文献
5.
Dr. Ondřej Jankovský Alena Libánská Daniel Bouša Prof. David Sedmidubský Dr. Stanislava Matějková Prof. Zdeněk Sofer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8627-8634
Partially hydrogenated graphene materials, synthesized by the chemical reduction/hydrogenation of two different graphene oxides using zinc powder in acidic environment or aluminum powder in alkaline environment, exhibit high electrocatalytic activities, as well as electrochemical sensing properties. The starting graphene oxides and the resultant hydrogenated graphenes were characterized in detail. Their electrocatalytic activity was examined in the oxygen reduction reaction, whereas sensing properties towards explosives were tested by using picric acid as a redox probe. Findings indicate that the high electrocatalytic performance originates not only from the hydrogenation of graphene, but also from unintentional contamination of graphene with manganese and other metals during synthesis. A careful evaluation of the obtained data and a detailed chemical analysis are necessary to identify the origin of this anomalous electrocatalytic activity. 相似文献
6.
Lu Wang Prof. Zdenek Sofer Prof. Radek Zboril Dr. Klara Cepe Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15444-15450
Doping of graphene materials with heteroatoms is important as it can change their electronic and electrochemical properties. Here, graphene is co‐doped with n‐type dopants such as phosphorus and halogen (Cl, Br, I). Phosphorus and halogen are introduced through the treatment of graphene oxide with PX3 gas (PCl3, PBr3, and PI3). Graphene oxides are prepared through chlorate and permanganate routes. Detailed chemical and structural characterization demonstrates that the graphene sheets are covered homogeneously by phosphorus and halogen atoms. It is found that the amount of phosphorus and halogen introduced depends on the graphene oxide preparation method. The electrocatalytic effect of the resulting co‐doped materials is demonstrated for industrially relevant electrochemical reactions such as the hydrogen evolution and oxygen reduction reactions. 相似文献
7.
Zusammenfassung Die Aromatizität eines 6- oder 5-Ringes drückt sich experimentell in der Ähnlichkeit der NMR-Kopplungskonstanten vicinaler Protonen, theoretisch in den benzoiden bzw. cyclopentadienyl-anionoiden Charakterordnungen aus. Diese Größen korrelieren gut miteinander.
Mit 1 Abbildung
Herrn Prof. Dr.Anton Wacek zum 75. Geburtstag gewidmet.
4. Mitt.:H. Sofer, O. E. Polansky undG. Derflinger, Mh. Chem.101, 1318 (1970). 相似文献
Aromaticity — Correlation between character orders and NMR coupling constants
Aromaticity of a 6- or 5-membered ring is expressed experimentally by the similarity of NMR coupling constants of vicinal protons and theoretically by the benzenoidic or cyclopentadienylanionoidic character orders, resp. Both types of values are correlated well.
Mit 1 Abbildung
Herrn Prof. Dr.Anton Wacek zum 75. Geburtstag gewidmet.
4. Mitt.:H. Sofer, O. E. Polansky undG. Derflinger, Mh. Chem.101, 1318 (1970). 相似文献
8.
Frontispiece: Hydrogenated Graphenes by Birch Reduction: Influence of Electron and Proton Sources on Hydrogenation Efficiency,Magnetism, and Electrochemistry 下载免费PDF全文
9.
Misfit‐Layered Bi1.85Sr2Co1.85O7.7−δ for the Hydrogen Evolution Reaction: Beyond van der Waals Heterostructures 下载免费PDF全文
Dr. Chun Kiang Chua Prof. Zdeněk Sofer Ondřej Jankovský Prof. Martin Pumera 《Chemphyschem》2015,16(4):769-774
Recent research on stable 2D nanomaterials has led to the discovery of new materials for energy‐conversion and energy‐storage applications. A class of layered heterostructures known as misfit‐layered chalcogenides consists of well‐defined atomic layers and has previously been applied as thermoelectric materials for use as high‐temperature thermoelectric batteries. The performance of such misfit‐layered chalcogenides in electrochemical applications, specifically the hydrogen evolution reaction, is currently unexplored. Herein, a misfit‐layered chalcogenide consisting of CoO2 layers interleaved with an SrO–BiO–BiO–SrO rock‐salt block and having the formula Bi1.85Sr2Co1.85O7.7?δ is synthesized and examined for its structural and electrochemical properties. The hydrogen‐evolution performance of misfit‐layered Bi1.85Sr2Co1.85O7.7?δ, which has an overpotential of 589 mV and a Tafel slope of 51 mV per decade, demonstrates the promising potential of misfit‐layered chalcogenides as electrocatalysts instead of classical carbon. 相似文献
10.
Liping Liao Bing Wu Dr. Evgeniya Kovalska Dr. Vlastimil Mazánek Dr. Martin Veselý Ivo Marek Lucie Spejchalová Prof. Dr. Zdeněk Sofer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(52):13235-13241
The intercalation of cations into layered-structure electrode materials has long been studied in depth for energy storage applications. In particular, Li+-, Na+-, and K+-based cation transport in energy storage devices such as batteries and electrochemical capacitors is closely related to the capacitance behavior. We have exploited different sizes of cations from aqueous salt electrolytes intercalating into a layered Nb2CTx electrode in a supercapacitor for the first time. As a result, we have demonstrated that capacitive performance was dependent on cation intercalation behavior. The interlayer spacing expansion of the electrode material can be observed in Li2SO4, Na2SO4, and K2SO4 electrolytes with d-spacing. Additionally, our results showed that the Nb2CTx electrode exhibited higher electrochemical performance in the presence of Li2SO4 than in that of Na2SO4 and K2SO4. This is partly because the smaller-sized Li+ transports quickly and intercalates between the layers of Nb2CTx easily. Poor ion transport in the Na2SO4 electrolyte limited the electrode capacitance and presented the lowest electrochemical performance, although the cation radius follows Li+>Na+>K+. Our experimental studies provide direct evidence for the intercalation mechanism of Li+, Na+, and K+ on the 2D layered Nb2CTx electrode, which provides a new path for exploring the relationship between intercalated cations and other MXene electrodes. 相似文献