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941.
Sergey A. Shteingolts Adam I. Stash Vladimir G. Tsirelson Robert R. Fayzullin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(48):e202200985
Intricate behaviour of one-electron potentials from the Euler equation for electron density and corresponding gradient force fields in crystals was studied. Channels of locally enhanced kinetic potential and corresponding saddle Lagrange points were found between chemically bonded atoms. Superposition of electrostatic and kinetic potentials and electron density allowed partitioning any molecules and crystals into atomic - and potential-based -basins; -basins explicitly account for the electron exchange effect, which is missed for -ones. Phenomena of interatomic charge transfer and related electron exchange were explained in terms of space gaps between zero-flux surfaces of - and -basins. The gap between - and -basins represents the charge transfer, while the gap between - and -basins is a real-space manifestation of sharing the transferred electrons caused by the static exchange and kinetic effects as a response against the electron transfer. The regularity describing relative positions of -, -, and - basin boundaries between interacting atoms was proposed. The position of -boundary between - and -ones within an electron occupier atom determines the extent of transferred electron sharing. The stronger an H⋅⋅⋅O hydrogen bond is, the deeper hydrogen atom's -basin penetrates oxygen atom's -basin, while for covalent bonds a -boundary closely approaches a -one indicating almost complete sharing of the transferred electrons. In the case of ionic bonds, the same region corresponds to electron pairing within the -basin of an electron occupier atom. 相似文献
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Huijuan Yang Hui Wang Shan Ji Yanjiao Ma Vladimir Linkov Rongfang Wang 《Journal of Solid State Electrochemistry》2014,18(6):1503-1512
Development of suitable supports has been proven as an important preparation process for high active catalysts of fuel cell. In this work, a carbon material was prepared by pyrolyzing cocoons with ferric chloride as activator, and then Pt nanoparticles (ca. 50 wt.%) were deposited on its surface. The characteristics of X-ray diffraction and transmission electron microscopy showed that the face-centered cubic structured Pt nanoparticles with nano-sized crystals interconnected each other via grain boundaries were formed on the surface of pyrolyzed cocoons. Afterwards, electrochemical results demonstrate that the nanostructured Pt supported on this support exhibits higher catalytic activity and CO tolerance than Pt nanoparticles supported on Vulcan carbon for methanol oxidation reaction. 相似文献
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The study of structure and dynamics of molecules: NMR spectra transformed by superfine coupling 下载免费PDF全文
Vladimir K. Voronov 《Magnetic resonance in chemistry : MRC》2015,53(3):188-193
In the present paper, the peculiarities of NMR phenomenon in paramagnetic systems are reported. Specifics of detection of high‐resolution NMR spectra transformed by superfine interaction are discussed. Concrete examples illustrate the modern possibilities of NMR application for the study of structure and dynamics of the molecular (multielectron) systems. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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