中文摘要：

运用密度泛函（DFT/B3LYP）方法对4种取代基（-NO2、-CN、-OH、-CH3）在8-羟基喹啉锂（Liq）五位上取代所形成的4种衍生物进行结构优化,并在此基础上应用含时密度泛函（TD-DFT）方法和单激发组态相互作用（CIS）分析了取代基对Liq前线分子轨道和电子光谱的影响。分析结果表明,不同性质的取代基对最高占据轨道（HOMO）电子云分布的影响趋势一致,而对最低空轨道（LUMO）电子云分布影响趋势不同。吸电子基使前线分子轨道能级降低,带隙增大,光谱蓝移。推电子基使前线分子轨道能级升高,带隙减小,电子光谱红移。推吸电子能力强的取代基对前线分子轨道和电子光谱的影响程度较大。

英文摘要：

By means of DFT/B3LYP method, the structure of 8-hydroxyquionline lithium （Liq） and its four derivates substituted by -NO2, -CN, -OH and -CH3 at position 5 were optimized. On the basis 3LYP-optimized structure, the influence of substituting group on the frontier molecular orbit and electronic spectrum of 8- hydroxyquionline lithium （Liq） has been analyzed by the singles configuration interaction （CIS） and time-dependent density functional theory （TD-DFT）. The results indicate that the substituting groups have the same effect on the highest occupied molecular orbital （HOMO）, while they have different effect on the lowest unoccupied molecular orbital （LUMO）. The electron-withdrawing groups make the molecular orbit energy level decrease, the band gap increase which lead to the blue shift of electronic spectrum while the electron-releasing groups make the molecular orbit energy level increase, the band gap decrease which lead to the red shift of the electronic spectrum.