中间体C60(CH3)-和产物C60(CH3)2的结构及产物

用INDO系列方法对C₆₀^2-与CH₃反应的中间体C₆₀(CH₃)^-进行理论研究,得到具有Cs对称性的构型。结果表明,CH₃加成到C₁₅上,将使与其相邻的双键碳(C₃₀)的电荷密度和自旋密度达极大值,故加成反应部位在C₃₀处;另外,C₁₅的对位C₁₂(或C₂₇)也较其它部位易于反应,且有两个反应场所,因而产物C₆₀(CH₃)₂可能为六元环上的1,2-加成和1,4-加成两种异构体的混合物。同时对两种加成产物的结构和电子光谱进行了理论研究,指认其电子跃迁,并讨论了其光谱红移的原因。

Theoretical Studies on the Structures of the Intermediate C_(60)(CH_3)-and the Product C_(60)(CH_3)_2 as Well as Spectroscopic Nature of the Product

Using INDO series of methods, we have performed the theoretical studies on the structure of the intermediate C60(CH3)- resulting from the reaction between C602- and CH3, and obtained the Cs geometry. It is indicated from the studies that the net charge and spin density on the atom C30 which is adjacent to C15 and locates on the double bond reach the maxima when CH3 is added to C1s, and thus the most reactive site is on C30 when C60(CH3)-reacts with second CH3.In addition, the opposite location of C1s that is C12 or C27 is easier to react than any other one except for C30 , moreover there are double location in this way;therefore the product C60(CH3)2 may be the mixture of the two isomers which are products of 1,2-addition and 1,4-addition on the six-membered ring. In the paper,we have made the theoretical exploration on the structure and the electronic spectrum of the product C60(CH3)2 and assigned the partial electronic transition, meanwhile discussed the reason about the redshift of its spectrum compared with C60.