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arXiv 1408.5161physics.chem-phcond-mat.softphysics.bio-ph
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界面氢键在“水上”催化中的作用

On the role of interfacial hydrogen bonds in "on-water" catalysis

Kristof Karhan, Rustam Z. Khaliullin, Thomas D. Kühne

摘要:

许多实验已经证明,当在非均相水乳液中进行时,许多种类的有机反应表现出增加的反应速率。尽管所观察到的“对水”催化效应和一些机理研究具有巨大的实际意义,但其微观起源仍不清楚。本文将第二代Car-Parrinello分子动力学方法推广到基于自洽电荷密度泛函的紧束缚方法,研究了偶氮二甲酸二甲酯与四环烷的Diels-Alder反应的“水上”催化作用.我们发现,悬挂的氢键暴露在水界面的过渡态的稳定起着显着较小的作用,在“对水”催化比以前已经建议。

英文摘要:

Numerous experiments have demonstrated that many classes of organic reactions exhibit increased reaction rates when performed in heterogeneous water emulsions. Despite enormous practical importance of the observed "on-water" catalytic effect and several mechanistic studies, its microscopic origins remains unclear. In this work, the second generation Car-Parrinello molecular dynamics method is extended to self-consistent charge density-functional based tight-binding in order to study "on-water" catalysis of the Diels-Alder reaction between dimethyl azodicarboxylate and quadricyclane. We find that the stabilization of the transition state by dangling hydrogen bonds exposed at the aqueous interfaces plays a significantly smaller role in "on-water" catalysis than has been suggested previously.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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