蒽醌及其羟基衍生物的密度泛函理论研究

运用密度泛函理论, 在B3LYP/6-31G*水平上, 对蒽醌及其羟基取代衍生物进行理论计算. 几何全优化的结果表明, 标题化合物均取平面构型, 分子内氢键对几何构型和电子结构影响很大. 基于简谐振动分析求得IR谱频率和强度, 并作了对称性分类和指认, 计算值与实验值良好相符. 运用含时密度泛函理论方法在相同水平上计算了标题物的电子吸收光谱, 发现蒽醌芳环取代衍生物的最低激发单重态均源自HOMO-LUMO(π→π*)跃迁. 基于振动分析, 由统计热力学求得了标题物的热力学性质.

Density Functional Theory Study on Anthraquinone and Its Hydroxyl Derivatives

Anthraquinone and its hydroxyl derivatives have been studied at the B3LYP/6-31G* level of density functional theory (DFT). The calculation results indicate that the title compounds have planar structures and exhibit strong intramolecular hydrogen bond, which has visible influence on the configuration and properties of the compounds. Normal-mode analyses have been performed to characterize the stable point and to determine the harmonic vibrational frequencies, and quite good results were achieved by comparing with the experimental data. The electronic spectra have been calculated too using the time-dependent DFT approach. The calculated results show that the first singlet exited state of the title compounds were obtained from the π→π* electron transition from the highest occupied molecular orbital to the lowest unoccupied molecular orbital. The standard thermodynamic properties of anthraquinones were calculated by the statistical thermodynamic method.