马隆甲在水中的紫外线吸收光谱主要由溶剂稳定型形状主导
Xuefei Xu1, Jingjing Zheng1, Donald G Truhlar1
1Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States.
Journal of the American Chemical Society
|June 18, 2015
概括
在水中,非化甲基 (MA) 乙醇对应物比化物更稳定. 溶剂稳定形状主导紫外线光谱,解释了实验观测.
科学领域:
- 计算化学计算化学
- 物理化学 物理化学
- 频谱学是一种光谱学.
背景情况:
- 甲 (MA) 存在于各种异构体中.
- 了解MA的形状稳定性和紫外线光谱对于化学研究至关重要.
- 溶剂对分子构成和电子性质的影响是研究的一个关键领域.
研究的目的:
- 为了研究不同环境中的malonaldehyde enol异构体的相对稳定性.
- 模拟和解释气相和水相中马隆甲的紫外线 (UV) 吸收光谱.
- 阐明溶剂稳定形态在观测到的光谱变化中的作用.
主要方法:
- 对八种醇异构体的自由能量计算 malonaldehyde.
- 使用密度函数理论 (DFT) 模拟紫外线吸收光谱.
- 基于密度 (SMD) 的溶解模型和总体平均垂直激发模型的应用.
主要成果:
- 在水中,MA的两个s-trans非化醇对应物比化醇 (CE) 对应物更稳定.
- 水中的紫外线光谱主要由溶剂稳定型形状占据主导地位,在气相中没有显著的人口.
- 与气相相比,合乙醇适应器在水中显示了轻微的红色变化.
结论:
- 溶剂的作用显著改变了malonaldehyde enol异构体的结构格局和稳定性.
- 在酸性水溶液中观察到的紫外线光谱主要是由于短暂的,溶剂稳定的构造.
- 计算方法准确地解释了不同阶段的malonaldehyde的实验紫外线吸收光谱.
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