This result is consistent with the experimentally observed features of short - life . that shows our model is reasonable . the parameters of the extended bbv model are as follows : the near neighbor interaction intension f = 0 . 75ev and the coefficient of the hubbard term u = 1 . 5ev 我們的模型參量為:近鄰格點(diǎn)電子相互作用強(qiáng)度作0 . 75ev ,同一格點(diǎn)的電子相互作用強(qiáng)度卜1 . 5ev 。