本文通过分析烷烃核磁共振碳谱（13C NMR）化学位移与生成焓之间的关系，提出由13C NMR化学位移的测定值来确定烷烃生成焓的新方法．用53个烷烃分子的13C NMR化学位移总和（SCS）、三键数（P3）以及碳原子数目（n）与生成焓实验值进行相关，所得回归方程的相关性良好（相关系数R=0.998 2，标准偏差S=3.5 kJ/mol）．进而，通过随机抽样和留一法证实该方程具有良好的稳定性和预测能力．将烷烃13C NMR化学位移与其生成焓定量联系起来，不仅有利于深入理解分子结构与性能关系，还为预测那些难于测定且费时的物理化学性质提供了新思路．
The quantitative relationship between the 13C NMR chemical shifts of alkanes and their formation enthalpy was studied. A new approach for calculating the formation enthalpy from the 13C NMR chemical shifts was proposed. The experimentally measured formation enthalpy values of 53 alkanes were correlated with the parameters SCS (the sum of chemical shift),P3 (path counts of length three bounds) and n (the number of carbon atoms). The regression results showed a good correlation (R=0.998 2,S=3.5 kJ/mol). The random sampling method and leave-one-out method were used to verify the stability and prediction ability of the model.
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