Abstract: In this paper, the quantum chemistry CNDO/2 introduced with external electric field perturbation was used to calculate the electronic polarizability of polyacence homologue substituted by chlorine, which comprises seven structures. Their energies were obtained by using AM1 method. Their stability, energies and changing regulation of electronic polariz-ability with the increase of structure unit were compared with each other.

Key words: External electric field perturbation, Electronic polarizability, Polyacence substituted by chlorine