本征态和高掺杂态聚乙炔电子的离域性

采用引入外电场微扰的量子化学方法，对具有Ａ型和Ｂ型碳链结构聚乙炔电子的极化率进行了推算，其中，Ａ型为碳－碳单双键交替结构，Ｂ型为碳－碳键长均一型结构，结果表明，Ｂ型聚乙炔电子的极化率明显大于Ａ型，或Ｂ型电子的离域性要明显高于Ａ型，其原因在于Ｂ型结构碳链的核对电子的吸引势能小于Ａ型。

The Electron Delocalizability of Polyacetylene in Eingen State and High-Level Doping State

The quantum chemical method intruduced within external electric field pertubation approach is used to calculate the electron polarizability of polyacetylene(PA) having A and B types carbon-chain structures. The A type carbon-chain has alternant carbon-carbon single and double bonds,and the B type has the uniform carbon-carbon bond lenth.The result shows that the electron polarizability of B type PA is obviously larger than that of Atype,i.e.the electron delocalizability of B-type PA is obviously larger than that of A-type.The further discussing shows that the reason inducing above result is that the attractive potential of nucleus to electron in B-type carbon chain is smaller than that in A-type.Our conclusion is much useful to explaining why the eigen state of PA having Atype structure is a semiconductor and the high-level doping state of PA having the B-type structure is a conductor.