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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
在HF/SbF中的超酸电友物种的性质:一个密度函数理论研究研究:5)
Pierre M Esteves1, Alejandro Ramírez-Solís, Claudio J A Mota
1Instituto de Química, Departamento de Química Orgânica, Universidade Federal do Rio de Janeiro, Cidade Universitária CT Bloco A, 21949-900, Rio de Janeiro, Brazil.
Journal of the American Chemical Society
|March 14, 2002
概括
这项研究使用密度函数理论来研究HF/SbF的超酸系统. 它确定了关键的电友性物种及其度,揭示了酸强度随着溶解而增加.
科学领域:
- 计算化学的计算化学
- 物理化学 物理化学
- 超酸性系统 超酸性系统
背景情况:
- 像HF/SbF(5) 这样的超酸在化学合成和催化中至关重要.
- 了解物种在超酸性介质中的行为对于控制反应至关重要.
- 以前的研究已经探讨了HF/SbF,但对物种分布和酸强度的详细计算分析仍在进行中.
研究的目的:
- 通过计算来研究HF/SbF超酸系统中的电友物种的结构和稳定性.
- 为了确定各种质子化物种的相对度.
- 为了评估这些物种的酸强度和溶解的影响.
主要方法:
- 密度函数理论 (DFT) 使用B3LYP/6-31++G** + RECP (Sb) 理论水平进行计算.
- 对潜在的电友物种进行几何优化.
- 计算平衡反应以估计物种度.
- 根据计算的特性评估酸强度.
主要成果:
- 计算了H(2)F(+).Sb(2)F(11)(-) 和H(3)F(2)(+).Sb(2)F(11)(-) 的几何形状并与实验数据保持一致.
- 在 1:1 HF/SbF ((5) 溶液中,主导物种是H ((+).Sb ((2) F ((11) ((-),H ((2) F (((+).Sb ((2) F ((11) ((-),H ((3) F ((2) +).Sb ((2) F ((11) ((-),和H ((4) F ((3) +).Sb ((2) F ((11))) 的度分别为36.9,16.8,36.9和9.4%.
- 酸强度随着给定离子的溶解度的增加而增加.
- 在超酸性质质子转移反应中,热效应是显著的.
结论:
- 该研究成功地确定和量化了HF/SbF超酸系统中的关键物种.
- 溶解在确定电友物种的酸强度方面发挥着至关重要的作用.
- DFT计算为超酸的复杂化学成分提供了宝贵的见解.
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