C18 Is a Polyyne
C18 Is a Polyyne
复制标题
DOI：
10.1021/ja00120a026
复制
发表时间：
1995-04
影响因子：
15
通讯作者：
Dietmar A. Plattner;K. N. Houk
中科院分区：
文献类型：
--
作者：
Dietmar A. Plattner;K. N. Houk
在过去的几年里，环状碳团簇在实验和理论上都引起了广泛的关注。1· 3· 4现在有越来越多的证据表明环碳在富勒烯的形成中起着决定性的作用。5-7尽管进行了大量的理论努力，但仍然缺乏对单环碳簇C n（n= 10-20）中的键合的共识。8我们提出了理论论证和计算证据，证明单环Cig具有扁平的环状多炔结构。C_n体系中的键交替趋势大于C_nH_n体系中的键交替趋势。以前对这个系统的计算导致了关于结构的错误结论。我们的研究还表明，密度泛函理论（DFT）在预测异构累积和炔结构的能量时总是出错。9然而，RHF和DFT计算的结合提供了关于潜在的双芳环碳，Cm，C14和C16的结构趋势的可靠结论。
Cyclic carbon clusters have stimulated much attention during the past years, both experimentally1 11· 2 and theoretically. 1· 3· 4 There is now growing evidence that cyclocarbons play a decisive role in the formation of fullerenes. 5-7 Numerous theoretical efforts notwithstanding, a consensus on the bonding in mono-cyclic carbon clusters C „(n= 10—20) is still lacking. 8 We present theoretical arguments and computational evidence that monocyclic Cig has a flattened circular polyyne structure. The tendency for bond alternation in the C „systems is greater than that in C „H „systems. Previous calculations on this system led to erroneous conclusions about structures. Our studies also show that density functional theory (DFT) errs consistently in the prediction of energies for isomericcumulenic and acetylenic structures. 9 Nevertheless, the combination of RHF and DFT calculations provides firm conclusions about structural trends in the potentially doubly-aromatic cyclocarbons, Cm, C14, and