这种四亚诺皮拉津化物是二分离子,[TCNP]2(2-). 两个电子的8中心结合
Juan J Novoa1, Peter W Stephens, Mahika Weerasekare
1Departament de Química Física and IQTCUB, Facultat de Química, Universitat de Barcelona, Av. Diagonal 647, 08028-Barcelona, Spain. juan.novoa@ub.edu
Journal of the American Chemical Society
|June 6, 2009
概括
(0) 复合物和四氨基 (TCNP) 之间的反应形成了一个TCNP基的阴离子二聚体. 这个二进制.
科学领域:
- 协调化学 协调化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 新型协调复合体的合成和表征对于开发新材料至关重要.
- 了解基离子二极体中的电子结构和结合,可以深入了解电子移位和分子间相互作用.
研究的目的:
- 为了研究二 () () 和1,2,4,5-四亚诺皮拉 (TCNP) 之间的反应.
- 为了描述由此产生的复合体和形成的TCNP基离子二极体.
- 使用计算方法阐明TCNP二元体的结合和稳定性.
主要方法:
- 合成的 [Cr(C(6) H(6)) ((2)][TCNP]复合体.
- 对被遮蔽的pi-[TCNP](2)(2-) 二次体进行晶体分析.
- 分子中的原子 (AIM) 分析.
- 密度函数理论 (DFT) 计算 (B3LYP/6-31+G(d)) 用于研究分子间相互作用.
主要成果:
- 反应产生了[Cr(C(6) H(6)) ((2) ]][TCNP],其中TCNP被减少到一个被遮蔽的pi-[TCNP](2) ((2-) 二次体.
- 电磁TCNP二聚体表现出3.14(2) Å的内部二聚体分离,C-C和N-N分离分别为3.29(2) 和3.42(2) Å.
- AIM分析表明,在二次体内存在一个2电子/8中心的C-C键.
- 计算研究揭示了排斥性的二分体内TCNP-TCNP相互作用 (-58.9 kcal/mol),稳定性主要是由TCNP基离子和对抗离子 (-209.8 kcal/mol) 之间的静电相互作用驱动的.
结论:
- TCNP基离子二极体的稳定性主要由与反的静电相互作用来决定,而不是直接的TCNP-TCNP结合.
- 观察到的结构扭曲,包括基曲,受到这些稳定电静电力的影响.
- 这项研究提供了对TCNP基离子二极体内的电子结构和分子间力量的详细了解.
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