探索乙烯和硫化单水合物中的构造景观,键和内部动力学
Weslley G D P Silva1,2, Tamanna Poonia1, Jennifer van Wijngaarden1,3
1Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
The Journal of chemical physics
|January 23, 2024
概括
旋转光谱检测显示,水与二乙烯 (DAE) 和二硫化物 (DAS) 有明显的相互作用. 水的结合影响了调节器的稳定性,DAS-水复合体由于较弱的键而表现出独特的道化.
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:
- 双乙烯 (DAE) 和双硫化物 (DAS) 是具有灵活结构的有机化合物.
- 了解水分子如何与这些化合物相互作用,对于预测它们在各种化学环境中的行为至关重要.
研究的目的:
- 为了研究二亚乙醇单 (DAE-w) 和二亚硫化物单 (DAS-w) 的构造性景观.
- 为了阐明水在通过键稳定特定变态体中的作用.
主要方法:
- 高分辨率的旋转光谱 (6-19 GHz).
- 量子化学计算 (B3LYP-D3(BJ) /aug-cc-pVTZ). 这是一个非常简单的方法.
- 非共价相互作用 (NCI) 和分子中原子的量子理论 (QTAIM) 分析.
- 对称性适应扰动理论 (SAPT).
主要成果:
- DAE-w表现出22个独特的合体,而DAS-w在6kJmol-1.1范围内有三个稳定的结构.
- 实验观察只证实了每个复合体的最低能量调整器.
- 水的结合改变了相对对应器的稳定性,特别是对于DAE.
- 这两种复合物都由两个分子间键 (HBs) 稳定.
- 在DAS-w中,初级HB比DAE-w更弱,更分散,导致DAS-w中的道分裂.
结论:
- 水不会改变DAE或DAS单体的首选适配体,但会影响其他适配体的稳定性.
- 观察到的适配体被双重分子间HBs稳定,其中涉及中央的异原子和基组.
- 在HB强度的差异解释了在DAS-w观察到的道化现象,表明更大的内部运动.
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