价值纽带理论揭示了多元体隐藏的非局部化激进性
Junjing Gu1, Wei Wu1, David Danovich2
1The State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry and College of Chemistry and Chemical Engineering, Xiamen University , Xiamen, Fujian 361005, China.
Journal of the American Chemical Society
|June 14, 2017
概括
聚烯电子结构主要是一个移动的二基体,而不是简单的交替键结构,尽管它仍然预测交替键长度. 这种化学二元性是一种基本现象.
科学领域:
- 量子化学
- 理论化学
- 有机化学
背景情况:
- 聚烯的电子结构和移位是基本的化学问题.
- 聚烯可能表现出二基形的特性,挑战传统的结合模型.
研究的目的:
- 使用计算方法研究聚烯的电子结构和移位特征.
- 作为链条长度的函数来确定多基因中的二基基质性质的程度.
主要方法:
- 使用了价值债券自一致场 (VBSCF) 的计算.
- 进行了不同链长 (C2nH2n+2,n=2-10) 的聚烯模拟.
主要成果:
- 对于n >= 5,多基因波函数向1,4-二基因波函数转移,随着链条长度的增加而增加.
- 尽管迪拉基体占主导地位,但基本的易斯结构预测了交替的结合长度.
- 移位能量显示对双键数的线性依赖: ΔEdel = -6.9 × n (kcal mol-1).
结论:
- 聚烯表现出一种'化学双重性原理',既具有局部性质,也具有局外性质.
- 迪拉基化特征在多元体中不是一个明确的物理性质.
- 在它们的电子结构的背景下,观察到未被替代的多元素的平面性.
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