【摘要】 在密度泛函理论(DFT)的B3LYP/6-31+G*水平上对硫靛染料发色体的几何结构进行优化计算,在获得基态稳定结构的基础上,应用含时密度泛函理论(TD—DFT)方法在相同水平计算电子吸收光谱。探讨了给电子基团对电子吸收光谱的影响。结果表明:给电子基团给电子能力的增强使光谱产生一定的红移。通过对前线轨道组成进行自然布居分析,揭示了硫靛染料的发光均源自分子中HOMO-LUMO(π→π*)电子跃迁。更多还原

【Abstract】 The geometrical structures of thioindigo chromophores were studied at the B3LYP/6-31+G level of density functional theory (DFT). Subsequently, the electronic absorption spectrum was calculated using the time-dependent density functional theory (TD-DFT) approach at the same level. The effect of the electron-donating groups on the electronic spectrum was investigated. The result indicated that absorption band of chromophore suffered bathochromic shift when electron-donating capability was increased. In addition, the frontier molecular orbital composition was analysed by natural population analysis (NPA), which indicated that the emission of thioindigo originated from the electronic HOMO-LUMO( π→π *)transitions.更多还原