选择性振动刺激和原子道化
Sergey V Ryazantsev1,2, Vladimir I Feldman1, Leonid Khriachtchev2
1Department of Chemistry, Lomonosov Moscow State University , Moscow 119991, Russia.
Journal of the American Chemical Society
|June 20, 2017
概括
研究人员观察到一种开物种的第一个形状光交换,即基 (HOCO). 他们发现矩阵稳定了 cis 调整器,通过振动激发和原子道化实现了 trans-cis 转换.
科学领域:
- 物理化学
- 光谱学
- 化学物理
背景情况:
- 碳氧基 (HOCO) 存在于 cis 和 trans 基,其中 trans 是较低能量的形式.
- 使用气和气的矩阵隔离技术用于研究基质物种.
- 对于反应动态来说,了解对应器稳定性和相互转换是至关重要的.
研究的目的:
- 在和矩阵中研究碳氧基 (HOCO) 和其化同位素 (DOCO) 的构造性行为.
- 探讨在开基物种中形成光交换的可能性.
- 阐明 cis 和 trans 的相互转换机制.
主要方法:
- 用红外 (IR) 光谱来研究和矩阵中的HOCO和DOCO.
- 选择性振动刺激用于诱导形状变化.
- 使用宽带红外光来观察自发的相互转换.
主要成果:
- 在基矩阵中,只观察到跨-HOCO 适配体,而DOCO 的 cis 和 trans 适配体都存在.
- 对于HOCO和DOCO来说,矩阵稳定了更高能量的cis调节器.
- 开物种的第一个形状光交换实例是通过选择性振动激发实现的.
- 原子道化被确定为矩阵中cis-to-trans衰变的机制,由动态同位素效应支持.
结论:
- 与矩阵相比,矩阵显著稳定了HOCO和DOCO的cis调整器.
- 可实现HOCO和DOCO的形状光交换,证明对基形状的控制.
- 原子道为开物种的cis-to-trans转换提供了一个独特的途径,在不同的矩阵中观察到不同的动态同位素效应.
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