在Mn{V}-Oxo物种中单元与三元反应:对实验证据进行理论预测
Tzuhsiung Yang1, Matthew G Quesne2, Heather M Neu1
1Department of Chemistry, The Johns Hopkins University , Baltimore, Maryland 21218, United States.
Journal of the American Chemical Society
|August 23, 2016
概括
高氧复合物表现出受自旋状态影响的反应性. 实验和计算研究显示单质反应机制的变化,而不是三质反应,影响氧化反应.
科学领域:
- 无机化学
- 计算化学
- 催化剂
背景情况:
- 在金属酶和催化剂中,高价值的金属氧物种至关重要.
- 计算研究表明更高的自旋状态可能会降低氧化反应障碍.
- 这些计算预测的实验验证具有挑战性.
研究的目的:
- 调查旋转状态对高价值 (V) 氧复合物的反应性的作用.
- 将计算结果与实验证据相关联,使用Z替代的离子.
- 了解替代剂对反应机制的影响.
主要方法:
- 对 ((V) -oxo复合物的详细计算研究.
- 用Z替代型硫醇进行反应性的分析.
- 用于评估旋转状态转换的最小能量交叉点计算.
- 解释替代效应的价值键模型.
主要成果:
- 对单点旋转状态观察到异常的机械变化,这取决于替代物的电子性质.
- 在三重旋转状态下没有观察到这种机械变化.
- 计算显示低旋转轨道合,使得旋转状态的相互转换不太可能.
- 实验反应性趋势支持单片面能够重现V形哈梅特图.
结论:
- - 氧- 科罗拉复合物的反应性受到自旋状态的显著影响.
- 单体状态表现出基于替代物效应的机理从电友性到核友性.
- 实验数据验证了计算模型,强调了在催化氧化反应中考虑自旋状态的重要性.
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