The isolated orbital method of non-self-consistent and self-consistent were used to assess charge transfer integral that under π conjugated organic semiconductor materials in different packing on pentacenes, which applied density functional theory B3LYP method of quantum chemistry based on 6-31G(d,p) level. On this basis, considering electric field effect on the charge transfer integral of different packing on pentacenes. The results showed that the isolated orbital of self-consistent method was relatively easy and accurate to calculate the charge transfer integral and agree with experimental data well, and also gave a good site energy including polarization. In addition, there was no effect on the pentacenes charge transfer integral of the packing under various situation of electric field strength.

Key words: charge transfer integral, pentacenes, isolated orbital method