电子结构决定了几何结构:键的长度在循环中交替[2n]碳
Xi Chen1,2,3, Xueyuan Yan1, Zihan Liu3
1College of Chemistry & Chemical and Environmental Engineering, Weifang University, Weifang, Shandong 261061, China.
The journal of physical chemistry. A
|October 3, 2024
概括
电子相关性,而不是几何学,导致循环[2n]碳中的双反芳香性. 密度函数理论 (DFT) 对较大的循环碳化合物是可靠的,但对较小的碳化合物 (如C6) 需要谨慎.
科学领域:
- * 计算化学 计算化学
- * 理论化学 理论化学
- * 有机化学 有机化学
背景情况:
- *电子结构和分子几何学之间的关系是一个长期存在的问题.
- * 循环[2n]碳具有双重反芳香性,但其起源仍有争议.
- *以前的研究还没有明确区分几何因素和电子因素.
研究的目的:
- * 为了阐明循环[2n]碳中双重反芳香性的起源.
- * 调查电子相关性与几何对称性的作用.
- * 评估密度函数理论 (DFT) 对于研究这些系统的可靠性.
主要方法:
- *密度函数理论 (DFT) 的计算.
- *密度矩阵重规范化组 (DMRG) 使用完整的活性空间自相一致场 (CASSCF) 方法.
- *电子结构和几何对称性的比较分析.
主要成果:
- * 偶成员循环[2n]碳中的双反芳香性主要是由电子相关效应驱动的.
- *仅凭几何对称性无法解释观察到的双重反芳香性.
- *电子关联稳定双反芳香性是一个关键概念.
- * DFT对于大于C14的环碳化合物是准确的.
- * DFT不准确地预测了C6的结构,突出了较小系统的局限性.
结论:
- *电子相关性是循环[2n]碳中双反芳香性的重要因素.
- *电子关联稳定双反芳香性的概念提供了一个新的视角.
- *在小型循环碳系统中使用DFT时建议谨慎使用;DMRG-CASSCF提供了更高的准确性.
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