掺杂聚乙炔中的孤子振动定域模

THE IRAV MODES AROUND CHARGED-SOLITON IN DOPED POLYACETYLENE

在SSH模型基础上,本文研究了掺杂聚乙炔链中杂质势对孤子振动模的束缚影响。不同边界条件下的数值计算发现Goldstone模将受到杂质钉扎并出现两个新的定域模g_1′和g_2′。另外,还得到了其它已知的定域模g_2,g_3和g_s,这些定域模随杂质势的敏感程度各有不同,在所取参数下取得了与实验基本一致的结果。

With a local potential of site-impurity in the frame work of the SSH model, the Coulomb effect of the dopant ions on the vibrational modes around the charged-soliton in doped poly-acetylene has been studied. The calculated results showed that the Goldstone theorem will be destroyed and the translation mode g1 will be pined by the dopant potential. At the same time, a new even-parity mode g' 1 has been found. The appearance of g1 and g'1 interpret well the broad peak at 930 cm-1. In addition, other localized modes have also been discussed.