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利用前文中建立的AM1级别上最大重迭对称性分子轨道计算方案,并结合最大键级杂化轨道方法,在对分子几何优化的基础上,计算系列化合物分子中各原子的电荷分布和杂化轨道组成系数,拟合出计算C—H及C—C偶合常数的简单关系式,计算各种分子中不同C—H键和C—C键偶合常数,所得计算值和实验数据较为吻合,两者相关系数和标准偏差:~1J_(CH)为0.982 0和6.020 5,~1J_(CC)为0.988 8和7.346 2,为计算~1J_(CH)和~1J_(CC)提供简便而直观的方法。建立的公式可预测新化合物中的C—H及C—C偶合常数,对新化合物的性质和结构及成键情况也能起到辅助推断作用,且在大分子体系的研究中极易推广。计算结果进一步表明所建AM1级别上最大重迭对称性分子轨道计算方法是可行的。
Based on the scheme of maximum overlapped symmetry molecular orbitals established in the previous paper and the combination of the maximum-order hybrid orbital method, based on the optimization of the molecular geometry, the charge distribution and the hybridization of each atom in the series of compound molecules are calculated Orbital composition coefficient, the simple relationship between C-H and C-C coupling constants is fitted and the coupling constants of different C-H bonds and C-C bonds in various molecules are calculated. The calculated values are in good agreement with the experimental data, and the two The correlation coefficients and standard deviations of ~ 1J_ (CH) were 0.982 0 and 6.020 5 and ~ 1J_ (CC) were 0.988 8 and 7.346 2, respectively, providing an easy and intuitive method for calculating ~ 1J_ (CH) and ~ 1J_ (CC) . The established formula can predict the C-H and C-C coupling constants of the new compounds, and can also help to infer the properties and structures of the new compounds as well as the bonding conditions. The formula can be easily popularized in the study of macromolecular systems. The calculation results further indicate that the method of calculating the maximum overlapped symmetry molecular orbitals at the AM1 level is feasible.