使用旋转光谱学和计算化学,探索基乙烯和硫化基乙烯的不同形状偏好
Tamanna Poonia1, Jennifer van Wijngaarden1,2
1Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
The Journal of chemical physics
|June 8, 2023
概括
对基乙烯 (AEE) 和基乙烯硫化物 (AES) 的形态分析揭示了由石化物电子特性驱动的独特结构. 光谱和计算方法阐明分子几何和能量景观.
科学领域:
- 物理化学 物理化学
- 分子光谱学 分子光谱学
- 计算化学的计算化学
背景情况:
- 了解分子构造对于预测化学和物理性质至关重要.
- 基乙烯 (AEE) 和基乙烯硫化物 (AES) 是研究素对分子结构影响的模型系统.
研究的目的:
- 调查和比较AEE和AEE的结构能量景观.
- 为了确定链接的石化原子 (氧与硫) 对分子几何学和稳定性的影响.
- 用理论分析合理化观察到的形状偏好.
主要方法:
- 福里埃变换微波光谱 (5-23 GHz) 用于实验数据采集.
- 密度函数理论 (B3LYP-D3(BJ) /aug-cc-pVTZ) 用于理论预测和结构分析.
- 对同位素物种 (13C和34S) 的分析,以获得实验性基态几何.
- 自然键轨道 (NBO) 和非共价相互作用 (NCI) 分析用于合理化.
主要成果:
- DFT计算预测了AEE (14) 和AES (12) 在一个狭窄的能量范围内的众多稳定对象.
- 实验频谱证实了AEE (3) 和AES (2) 两种最低能量的适配器的主导地位,它们在侧链安排上有所不同.
- 甲基内部旋转障碍被确定为AEE符合I和II (约. 12.2 kJ mol-1). 这样一来,我们就有了.
- 实验几何学揭示了对石化原子的依赖,这与氧气到硫的杂交减少一致.
- NBO和NCI的分析强调了素单对相互作用在决定形状偏好方面的作用.
结论:
- AEE和AES的构造格局复杂,有多个竞争性构造.
- 连接素原子的电子特性显著影响分子结构和稳定性.
- 涉及单独的石化对的相互作用是这些分子结构偏好的关键驱动因素.
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