环戊二噻吩中的硫原子被CH2、SiH2取代对化合物光电性质影响的理论研究

有机电致发光材料是国际上的研究热点之一。本文采用量子化学方法,研究了环戊二噻吩CH2和SiH2取代对其与2,1,3-苯并噻二唑和三苯胺的化合物光电性质的影响。研究结果表明,CH2取代对母体分子的电子和光谱性质的影响比SiH2取代明显。SiH2取代使吸收和发射光谱的振子强度增大的程度大于CH2取代,更有利于发光强度的提高。CH2和SiH2取代衍生物的空穴和电子重组能的差值极小,可以作为有机电致发光二极管中双极性电荷传输材料。静电势能结果表明,SiH2取代衍生物的稳定性高于母体分子的稳定性。通过探索分子结构与性质间关系,为实验设计合成新的有机电致发光材料提供了理论支持。

Theoretical Investigation on the Optoelectronic Properties of CH2/SiH2 Substituted Cyclopentadithiophene Derivatives

The investigation for organic electroluminescent materials has become a fascinating field.The influence of CH2 and SiH2 substitutions on the optoelectronic properties of the cyclopentadithiophene derivatives was studied by quantum-chemical methods.The results showed that CH2 substitution induced more pronounced effect on the electronic and optical properties of the pristine molecule than those of SiH2 one;noticeably,SiH2 substitution had more positive effect on the oscillator strength of the absorption/emission spectra than that of CH2 substitution.Moreover,the differences between hole and electron reorganization energies of CH2 and SiH2 substituted derivatives were very small so they can be used as better ambipolar transportation materials in organic light-emitting diodes(OLEDs).The calculated results of electrostatic surface potentials suggested the stability of SiH2 substituted derivative was higher than that of the pristine molecule.The results can be used for the design and synthesis of novel organic light-emitting materials.