中文摘要：

为了改善聚芴的载流子注入特性,采用密度泛函理论B3LYP/6-31G＊方法计算比较了芴、芴-联吡啶和芴-菲咯啉低聚物的几何结构、电子结构、最低激发能及重组能等,并外推到相应聚合物.结果发现：联吡啶/菲咯啉含氮芳杂环的缺电子性质能够诱导聚芴的最高占据轨道（HOMO）和最低空轨道（LUMO）能级分别下降0.45/0.47eV和0.32/0.38eV,提高电子注入能力的同时,调控载流子注入平衡;联吡啶单元的引入导致电子和空穴重组能升高（降低聚芴的载流子迁移率）,而芴-菲咯啉共聚物显示了与聚芴相似的迁移性能.

英文摘要：

To improve the carrier-injection of polyfluorene,oligomers of polyfluorene,fluorene-bipyridine,and fluorene-phenanthrolin copolymers were theoretically studied for their geometries,electronic structures,excitation energies,and reorganization energies by density functional theory at the B3LYP/6-31G＊ level.We evaluated the properties of the corresponding polymers by linear extrapolation.We found a large decrease of about 0.45/0.47 eV and 0.32/0.38 eV for the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） levels,respectively,after the introduction of electron-deficient bipyridine/phenanthrolin into polyfluorene.These molecules improved the electron injection ability and the balance of carrier-injection in polyfluorene systems.Additionally,the reorganization energy increased for both electron and hole transports upon the incorporation of bipyridine,which resulted in worse carrier mobility.However,the fluorene-phenanthrolin copolymer showed a similar charge transport property to polyfluorene.