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采用量子化学限制性Hartree Fock方法(RHF)和多参考态组态相互作用方法(MRCI),对渺位缩合和迫位缩合稠环芳烃的基态和激发态的最高活性碳位进行了研究。前线轨道的能级研究表明,基态时随着环数的增加,渺位缩合稠环芳烃的前线轨道能级差从1065 kJ/mol逐渐减小到976.4 kJ/mol,说明随着环数的增加,渺位缩合稠环芳烃分子的稳定性逐渐降低,分子反应活性逐渐增强。而迫位缩合稠环芳烃由于分子内部芳香环的结合程度和碳原子的共用程度不一致导致处于基态时前线轨道能极差并没有随着芳环数的增加呈现出线性行为。进一步,通过比较C原子的Mulliken电荷,以及不同位置C-C键的键级和键长研究了稠环芳烃的亲核加氢反应的最高活性碳位。结果表明,处于基态时,渺位缩合稠环芳烃的最高活性碳位出现在内侧芳环的外侧碳位上,而迫位缩合稠环芳烃的最高活性的碳位出现在外侧芳环的外碳位置;处于激发态时,大多数渺位缩合、迫位缩合稠环芳烃的最高活性碳位与基态是重合的,部分稠环芳烃的最高活性碳位会发生转移。
Quantum chemical constrained Hartree Fock method (RHF) and multi-reference state configuration interaction method (MRCI) were used to investigate the ground state and excited state highest condensed carbons of the condensed and condensed condensed aromatic hydrocarbons. The study of the frontier orbital energy levels shows that the frontier orbital energy gap of the condensed condensed aromatic ring decreases from 1065 kJ / mol to 976.4 kJ / mol with the increase of the number of rings in the ground state, indicating that as the number of rings increases, The valence condensation condensed aromatic ring molecules gradually reduce the stability of molecular reaction gradually increased. Compacted condensed aromatic hydrocarbons due to intramolecular aromatic ring and carbon atoms are not the same degree of sharing resulting in the ground state when the frontier orbital energy does not show an increase with the number of aromatic rings linear behavior. Furthermore, the highest carbon positions in nucleophilic hydrogenation of condensed aromatic hydrocarbons were studied by comparing the Mulliken charge of C atoms with the bond length and bond length of C-C bonds at different positions. The results show that at the ground state, the highest carbon atom of the condensed condensed aromatic ring in the valence state appears on the outer carbon ring of the inner aromatic ring, while the carbon atom of the most active carbon of the condensed aromatic ring in the condensed state appears on the outer carbon of the outer aromatic ring In the excited state, most of the valences are condensed and the highest carbon positions of the condensed condensed aromatic hydrocarbons are coincident with the ground state, and some of the most active carbons of condensed aromatic hydrocarbons will shift.