摘要
采用密度泛函理论(DFT)B3LYP/6-31G方法对三-(8-羟基喹啉)铝(Alq3)及3种二氟取代衍生物进行了计算研究,分析比较了4种配合物的前线分子轨道组成、轨道能级、电离能、电子亲和势及重整能等性质的同异.结果表明,各配合物的电子跃迁主要发生在不同配体之间的π→π*跃迁.苯酚环上6,7-二氟取代使电子跃迁能力降低,而5,6和5,7-二氟取代使电子跃迁能力提高.二氟取代均可较显著地使得最低空轨道的能级降低,电子亲和势升高,有利于电子注入.此外,5,7-二氟取代后配合物的电子重整能和空穴重整能显著增大,材料稳定性降低.因此,综合比较各因素的影响,Alq3在6,7位置吸电子基团取代有望成为优良的电子材料.
The elecero-transpore nature of tris-8-hydroxyquinolate-aluminum (Alq3) and its derivatives have been studied by the density functional theory (DFT) with B3LYP functional. The frontier molecular orbital characteristics and energy level of Alq3 and its derivatives have been analyzed systematically. The results indicate that the emissions of Alq3 and its derivatives originate from the electron π→ π^* transitions between different ligands, the difluoro-substituted groups make HOMO-LUMO gaps, ionization potentials and electron affinities are conducive to improve the electron injection and charge transfer properties. The change in difluoro-substituted position on 8-hydroxyquinoline ligand is a powerful approach for tuning the ability of electron injection.
出处
《陕西师范大学学报(自然科学版)》
CAS
CSCD
北大核心
2008年第6期58-62,共5页
Journal of Shaanxi Normal University:Natural Science Edition
基金
陕西省自然科学基金资助项目(2006B12)