电子关联对聚乙炔中双激子湮灭过程的影响

摘要

在SSH哈密顿基础上引进弱电子关联，对反式聚乙炔链中双激子的湮灭过程实施了分子动力学模拟．电子关联的引入延缓了链中激子的湮灭过程，关联强度U=0eV时，激子的湮灭时间约在t=84fs，计入四个近邻格点上的弱电子关联作用，湮灭时间明显减慢，约为t〉100fs．随着弱关联强度的增加，湮灭时间逐渐延长．计算结果表明，在计算有机材料激子快速响应过程中计入电子关联是十分必要的．%Adding a weak electron correlation to the Su-Schrieffer-Heeger model, we have simulated the annihilation of a bi-exciton in trans-polyacetylene. It is showed that the weak electron correlation delays the annihilation of bi-exciton, and the relaxation time of annihilating a bi-exciton is prolonged from 84fs to more than 100fs. The weak correlation does slow the annihilation process. In the calculation of fast response process of excitons, considering the electron correlation is very necessary.