Estimation of Formation Enthalpy for Alkanes from 13C NMR Chemical Shifts

• Main Authors: WU Ya-xin, CAO Chen-zhong, TENG Li-li
• Format: Article
• Language: zho
• Published: Science Press 2019-03-01
• Series: Chinese Journal of Magnetic Resonance
• Subjects: alkanes; formation enthalpy; 13C NMR; chemical shift; path counts of length three bounds (P3)
• Online Access: http://html.rhhz.net/bpxzz/html/20190107.htm

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.