Electronic Structure of Doped Trans-Polyacetylene

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C 24H 26) +n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated by CNDO/2 method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.