孤立球 (BCO) n 和 (CH) n 子的结构和能量
Hai-Shun Wu1, Xiao-Fang Qin, Xiao-Hong Xu
1Department of Chemistry, Shanxi Normal University, Linfen, 041004, China.
Journal of the American Chemical Society
|February 17, 2005
概括
- 碳 - 氧 (BCO) 子表现出较低的应变能量,并且与碳化合物 (CH) 子相比更喜欢三环环. 大型BCO系统更喜欢管状结构而不是子.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
背景情况:
- 异球类比对于预测新化学物种的特性至关重要.
- 了解多面体的稳定性和结构偏好是材料设计的关键.
研究的目的:
- 研究和对比多面体 (CH) n和 (BCO) n物种的结构和能量特性.
- 探索环形大小和结构对碳和-碳-氧系统稳定性的影响.
主要方法:
- 使用B3LYP函数的密度函数理论 (DFT) 计算.
- 应变能量的比较分析和首选的几何配置.
- 平面和多面体系统的建模.
主要成果:
- - 碳 - 氧 (BCO) n 子具有比它们的 (CH) n 子显著更低的应变能量.
- 稳定 (BCO) n多面体 (n ≥ 10) 最好采用最多有三个环的结构.
- 平面 (HBCO) n 环表现出较低的应变能量,三环 (HBCO) 3 环非常稳定.
- 较大的 (BCO) n系统倾向于形成管状结构,而不是封闭的子.
结论:
- 在 (BCO) n中和氧的电子结构显著改变了与碳化合物相比的稳定性和结构偏好.
- 在 (BCO) n系统中,对三环的偏好为设计应变材料提供了新的途径.
- 管状结构代表大 (BCO) n系统的稳定动机,与典型的碳行为有所区别.
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