避免过高价值:简单的替代BrF3和BrF5分子. 化HBrF2和HBrF4的结构,热化学和电子亲和力
Qianshu Li1, Liangfa Gong, Yaoming Xie
1Department of Chemistry, School of Science, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
Journal of the American Chemical Society
|November 13, 2004
概括
这项研究揭示了化复合物,而不是高价结构,是HBrF (n) (n=2,4) 最稳定的形式. 这些复合体具有键,并具有显著的电子亲和力,与相关的素系统相比较.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 无机化学 无机化学 有机化学
背景情况:
- 密度函数理论 (DFT) 和混合的Hartree-Fock/DFT方法对于预测分子性质至关重要.
- 了解化化合物的稳定性和反应性在化学中很重要.
研究的目的:
- 研究化HBrF (n) 和它们的离子 (n=2,4) 的分子结构,热化学和电子亲和力.
- 为了确定最稳定的配置,确定超价结构或复杂结构是否占主导地位.
主要方法:
- 采用了五种DFT和混合的Hartree-Fock/DFT方法.
- 使用了带有扩散函数的双泽塔加极化 (DZP++) 基础集.
- 计算了分子结构,热化学和电子亲和力.
主要成果:
- 预计HBrF (n) /HBrF (n) (n=2,4) 的全球最小值是键复合体,而不是超价结构.
- 对HF的有利解离,HF是一种具有高解离能量的分子,推动了这些复合物的形成.
- 使用BHLYP计算的HBrF(2) 的3.69 eV和HBrF(4) 的4.38 eV的电电子亲和度 (EA(ad)) 使用BHLYP.
结论:
- 与结合复合体相比,HBrF (n) 的超价结构在能量方面不利.
- 这些复合物的稳定性受到HF的强烈解离能量的影响.
- 计算的电子亲和度与包含Br,Cl和F的相关系统的电子亲和度相当.
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