应用基团键贡献法计算烷烃和环烷烃的折光指数

根据分子中基团的特性和连接性，发展了一种直接根据分子结构信息计算烷烃和环烷烃折光指数的新方法－基团键贡献法，该方法既考虑分子中基团的特性，又考虑基团之间的连接性(化学键)，同时具有基团贡献法和化学键贡献法的特点。应用基团键贡献法对950种烷烃和环烷烃折光指数的计算结果表明，计算值与实验值的一致性令人满意，平均误差0.11%，进一步对聚乙烯、聚丙烯和聚1-丁烯等聚合物的折光指数进行预测，也取得了令人满意的结果。

Calculating the refractive index of alkane and cycloalkane using the group bond contribution method

Based on characteristics and connectivity of the groups in molecules, the group bonds can be got to describe the molecular structure. A kind of group bond was a chemical bond with two groups, therefore the group bonds contained the property information of and connectivity information of the groups in molecules. Group bonds can be got directly from molecular structure, and can be used to calculate the property of molecules. A new method, the group contribution method, was developed that can be used to calculate the refractive index of alkanes and cycloalkanes from molecular structure. The calculated results showed that the calculated refractive indexes of alkanes and cycloalkanes using the group bond contribution method were in good agreement with the experimental data, the mean relative deviation was 0.11% for 950 alkanes and cycloalkanes, and the group bond contribution method had advantages over the group contribution method and chemical bond contribution method.