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Electron Spin Resonance Micro-imaging of Live Species for Oxygen Mapping
Published on: August 26, 2010
氧基的振动 氧基的振动
J Spanget-Larsen1, M Gil, A Gorski
1National Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, Colorado 80401, USA.
Journal of the American Chemical Society
|November 8, 2001
概括
研究人员使用红外光谱在矩阵中研究了基 (C(6) H(5) O). 他们详细说明了它的振动分配,并发现CO拉伸振动可以指示其环境的极性.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 量子化学 是一个量子化学.
背景情况:
- 基是各种化学过程中的关键中间体.
- 了解它的振动特性对于描述它的结构和反应性至关重要.
- 以前使用溶液共振拉曼光谱的研究提供了有限的振动数据.
研究的目的:
- 为了准备和描述低温子矩阵中的基.
- 赋予基及其同位素标记变体的红外 (IR) 振动.
- 研究环境对基的振动频率的影响.
主要方法:
- 在矩阵中的基的光化学制备.
- 红外吸收光谱对C(6) H(5) O,C(6) D(5) O,和1-(13) C(12) C(5) H(5) O.O.进行检测.
- 在光导向样本上进行IR线性二元化测量.
- 确定绝对IR强度的方法.
- 同位素转移分析. 同位素转移分析.
- 量子化学计算 (B3LYP/cc-pVTZ) 进行.
主要成果:
- 检测了基的大部分红外活性基本振动,其中许多以前没有观察到.
- 通过实验和计算方法的结合,对基振动进行了详细的分配.
- 与基于溶液的拉曼研究相比,观察了显著的频率变化.
- 确定CO拉伸振动对环境极性高度敏感.
结论:
- 基矩阵中的基的振动光谱提供了详细的描述.
- 环境影响,特别是在极地介质中,可以诱导结构变化,如增加类特征.
- 碳化合物拉伸频率可以作为可靠的探测器来确定基环境的极性.
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