Aromaticity on the fly: cyclic transition state stabilization at finite temperature.
Aromaticity on the fly: cyclic transition state stabilization at finite temperature.
复制标题
动态芳香性：有限温度下的循环过渡态稳定。
DOI：
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发表时间：
2010
影响因子：
2.9
通讯作者：
A. Stirling
中科院分区：
文献类型：
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作者：
T. Rozgonyi;Albert Bartók;A. Stirling
用无偏从头算分子动力学方法研究了高温下周环反应的过渡态。我们发现，尽管存在显著的热原子运动，但分子内重排的过渡态在高温下仍保持芳香。动态过渡态的结构、磁性和电子性质表现出亲和性和芳香性。自由能计算也支持了过渡态理论对当前重排反应的有效性。计算结果表明，即使在高温下，循环离域也对同步热原子运动具有很强的作用。
We study the transition state of pericyclic reactions at elevated temperature with unbiased ab initio molecular dynamics. We find that the transition state of the intramolecular rearrangements for barbaralane and bullvalene remains aromatic at high temperature despite the significant thermal atomic motions. Structural, magnetic, and electronic properties of the dynamical transition state show the concertedness and aromatic character. Free-energy calculations also support the validity of the transition state theory for the present rearrangement reactions. The calculations demonstrate that cyclic delocalization represents a strong force to synchronize the thermal atomic motions even at high temperatures.