赫克尔方法的密度矩阵适应用于弱共价网络
Laura Van Dorn1, Andrei Sanov1
1Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, USA. sanov@arizona.edu.
Physical chemistry chemical physics : PCCP
|February 5, 2024
概括
在弱共价网络中电荷定位是一种内在的属性,不需要外部因素. 这种现象源于几何放松,在各种单体中观察到.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 材料科学 材料科学 材料科学
背景情况:
- 赫克尔分子轨道 (MO) 理论为理解电子结构提供了一个框架.
- 自相一致的密度矩阵形式对于准确的电子计算至关重要.
- 了解共价网络中的电子反应性是预测材料性质的关键.
研究的目的:
- 适应Hückel MO理论来描述弱共价网络中的电子反应.
- 使用新型模型研究单体链中的电荷共享和局部化.
- 探索驱动电荷定位在共价系中的内在因素.
主要方法:
- 开发了一种基于Hückel MO理论和密度矩阵形式主义的合单体模型.
- 嵌入的可变债券和库伦积分取决于密度矩阵元素 (债券订单,部分费用).
- 利用数据驱动的建模,对实验或初始数据进行培训,以提高准确性.
主要成果:
- 预测X±集群中的电荷倾向于在2-3个单体上定位.
- 这一预测得到了He+,Ar+, (glyoxal) -和 (biacetyl) -等众所周知的集群家族的证实.
- 证明电荷定位发生在一个连贯的共价状态下,没有热激发或非共价扰动.
结论:
- 在弱共价网络中电荷定位是一种内在的特征,由几何放松驱动.
- 这种局部化基本上与共价键顺序和平衡键积分之间的相关性有关.
- 这些发现意味着电荷定位不需要外部因素,如溶解或脱凝.
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