摘要
用密度泛函方法对联苯桥联的PPV齐聚物(TSB)的反式结构进行全优化,得到基态分子的最优几何构型和电子能级,并用ZINDO和TDDFT方法分别计算其吸收光谱,分析了不同类型的端位取代基团对前线分子轨道能量和能隙的影响.结果表明,联苯桥联后的PPV齐聚物在结构上形成了链间交叉链内扭曲的构象,这种交叉扭曲的构象降低了分子的对称性,减弱了共轭分子在固体中的ππ堆积作用,这可能是减少荧光猝灭效应,提高固体发光器件效率的重要原因.
We fully optimized the trans-structures of PPV oligomer with biphenyl bridge using DFT/B3LYP method with Gaussian 98 software and gained thc most rational geometry structure of ground state and electronic energy level. Then the absorption spectra data are calculated at ZINDO and TD-DFT levels of theory. We also analyzed the factors that different substituent groups connecting to the end of molecules impacted the frontier molecular orbitals and the energy gap. The results indicate that the PPV oligomer with biphenyl bridge is a cross form between two chains and tortuose derivative in the same chain. It reduces molecular symmetry and weakens π-π stacking effect among conjugated light-emitting diodes can increase fluorescence molecules in solid. This is perhaps the important factor that quantum efficiency.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第3期510-514,共5页
Chemical Journal of Chinese Universities
基金
国家'九七三'计划(批准号:2002CB613403)
国家自然科学基金(批准号:50303007
50473001)资助.
关键词
PPV齐聚物
密度泛函
基态构型
电子能级
吸收光谱
PPV oligomer
DFT
Structure of ground state
Electronic energy level
Absorption spectrum
作者简介
联系人简介：马於光（1963年出生），男，教授，博士，博士生导师，主要从事聚合物光电功能材料研究．E-mail：ygma@jlu．edu．cn
