β位取代基对咔咯锰(Ⅴ)氧配合物电子吸收光谱的影响

Effect of β-Substituents on the Electronic Absorption Spectra of Manganese(Ⅴ)-oxo Corrole Complexes

采用含时密度泛函理论(TDDFT)和B3LYP方法对一系列β位咔咯锰(V)氧配合物的几何结构、前线轨道、自然键轨道和电子吸收光谱进行了计算。并探讨了β位取代基对咔咯锰(V)氧配合物电子吸收光谱的影响。结果显示β位取代基效应中的空间效应是能导致该体系电子吸收光谱Soret带和Q带红移。β位取代基的空间位阻大时,导致配合物的咔咯环产生严重扭曲,引起Soret带和Q带吸收峰的ΔE能隙减小,导致Soret带和Q带发生红移。

Time-dependent density functional theory （TDDFT） calculations using the B3LYP method were used to investigate the effect of β-substituents on the electronic absorption spectra of a series of manganese（V）-oxo corrole complexes. The geometries, frontier molecular orbitals, and energies of the complexes were analyzed. The calculated results indicate that the steric effect of the β-substituents is the factor controlling the red-shift of the Soret bands and Q bands in these complexes. The sterically hindered β-substituents cause twisting of the corrole ring structure, which leads to reduced orbital energy gaps and a red-shift of the Soret bands and Q bands.