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密度对布伦斯特德α的贡献,用于NAD+类似物之间的化物转移
In-Sook Han Lee1, Kim-Hung Chow, Maurice M Kreevoy
1Department of Science Education, Kangwon National University, Chuncheon 200-701, Korea.
Journal of the American Chemical Society
|June 27, 2002
概括
马库斯理论准确地预测了化物转移反应速率,显示了替代物位置影响的Bronsted alpha. 这项研究证实了有关含酸的预测,类似于尼古丁胺胺氨基二核酸 (NAD+).
科学领域:
- 化学动力学 化学动力学
- 反应机制的反应机制
- 有机化学 有机化学
背景情况:
- 化物转移反应是生物和化学过程的基础.
- 马库斯理论为理解电子和原子转移反应提供了一个框架.
- 尼古丁胺胺二核酸 (NAD+) 是一个重要的生物化物受体.
研究的目的:
- 实验证实马库斯理论对化物转移反应的预测.
- 为了研究替代剂位置对反应动力学的影响.
- 将实验结果与理论计算进行比较.
主要方法:
- 研究了化物转移反应,涉及异环,含的阳离子.
- 测量反应速度和平衡常数.
- 运用变量过渡状态理论和线性三原子模型进行计算.
- 分析了动态同位素效应.
主要成果:
- 证实了替代剂在供体或受体中的位置会影响布伦斯特德α值 (0.67对0.32).
- 在两个替代位点上观察到一致的紧密度参数 (tau ≈ 0.66).
- 使用线性三原子模型进行理论计算,半量化模仿实验结果.
- 纠正了潜在函数的波恩充电项中的一个之前的错误.
结论:
- 马库斯理论成功地描述和统一了实验和计算的化物转移速率常数.
- 线性三原子模型为理解原子转移反应提供了一个有用的概念工具.
- 替代物对化物转移动学的效应通过马库斯理论得到了很好的解释.
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