洞穴类型和扩散性质子转移在7-基诺林中. (NH(3)) (n) 集群是指一个集群
M Meuwly1, A Bach, S Leutwyler
1Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3000 Bern 9, Switzerland.
Journal of the American Chemical Society
|November 15, 2001
概括
通过光谱学和DFT计算,研究了7-基诺林氨集群中的质子转位. 发生了Grotthus类型的质子跳跃,其中一个步骤涉及复杂的重组和扩散.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 计算化学计算化学
背景情况:
- 质子转移是化学和生物系统的基础.
- 氨集群作为模型系统,用于研究结网络中的质子动态.
- 7-基 (7-HQ) 提供了一个分子平台,用于启动和观察质子转位.
研究的目的:
- 为了研究在7-基因中沿氨线进行质子转位. (NH3) 集群. (NH3) 集群. (NH3) 集群. (NH3) 集群. (NH3) 集群. (NH3) 集群.
- 为了模拟有限大小的系统,沿着结溶剂链进行质子转移.
- 描述质子转移事件的能量和机制.
主要方法:
- 使用激光光谱学的实验调查.
- 使用哈特里-福克和密度函数理论 (DFT) 的理论计算.
- 稳定的zwiwterionic集群和过渡状态的表征.
主要成果:
- 观察到7-HQ的质子转位和重质子化,形成了基托 tautomer.
- 外能质子转移以形成zwitterion发生在n=5或6的值集群大小.
- 对于大多数转移步骤,已经确定了具有较低障碍的Grotthus型质子跳跃机制.
- 一个阶段由于结构重组和扩散运动而表现出高的障碍.
结论:
- 氨线可以促进质子转移到7-基诺林集群中.
- 该研究阐明了这些模型系统中质子转移的机制和能量.
- DFT和实验方法为复杂的质子动态提供了互补的见解.
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