顺序翻转:在水机中的捐赠者-接受者交换机制
Xinrui Yang1, Rui Liu1, Ruiqi Xu1
1Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China. wangzg@jlu.edu.cn.
Physical chemistry chemical physics : PCCP
|August 9, 2023
概括
一个新的顺序翻转 (SF) 机制驱动了水修剪器中的供体接受体交换 (DAE),与质子转移 (PT) 不同. 这种在65K以上占主导地位的SF工艺提供了一种方法来区分使用循环二元论的DAE机制.
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:
- 捐赠者-接受者交换 (DAE) 是键网络重组 (HBNR) 的关键机制,通常涉及质子转移 (PT).
- 对于基本的化学过程来说,了解像trimers这样的小水集群中的DAE至关重要.
研究的目的:
- 识别和描述水机中的一个新的DAE机制.
- 在能源障碍和结果方面,将新机制与已建立的PT过程进行比较.
- 探索用于实验区分不同DAE途径的方法.
主要方法:
- 使用高精度*ab initio*计算来建模DAE机制.
- 计算了顺序翻转 (SF) 和集体旋转的潜在能量障碍.
- 进行了反应速率分析,包括量子道效应.
- 分析了SF-DAE和PT-DAE之间的基质差异.
主要成果:
- 通过水分子的顺序翻转 (SF) 发现了一种新的DAE机制.
- 与集体旋转 (~1.7 eV) 相比,SF过程具有明显较低的电位障碍 (0.262 eV).
- 与PT-DAE相比,SF-DAE表现出明显的性,通过循环二元化实现潜在的差异化.
- SF在65K以上的DAE中占主导地位,而PT在65K以下占主导地位,这表明存在温度依赖的竞争.
结论:
- 序列翻转 (SF) 是水修剪器中供体-接受体交换 (DAE) 的主要途径,与之前假定的质子转移 (PT) 主导相对立.
- SF-DAE的较低的能量屏障和明显的性特征为键网络的重新安排提供了新的见解.
- 这一发现大大提高了对DAE机制及其实验观测的理解.
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