Chinese Journal of Magnetic Resonance

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EQUILIBRIUM ELECTRONEGATIVITY AND 13C NMR CHEMICAL SHIFTS OF ALKANES

NIE Chang-ming,WEN Song-nian   

  1. Department of Chemistry and Chemical Engineering, Nanhua Univertsity, Hengyang 421001
  • Received:2000-11-27 Published:2001-03-05 Online:2001-03-05
  • Supported by:

    湖南省教育厅资助项目(00C178).

Abstract:

In this paper, the atomic equilibrium electronegativity in a molecule has been defined and the model of 13C NMR chemical shifts of alkanes has been studied with the atomic equilibrium electronegativity and the structural information parameters NiH(em=0, α, β, γ) and NjC(j=α, β, γ). The results indicate that the
13C NMR chemical shifts of alkanes can be described as follows:
CS=-1736.776+755.118AEE+5.2539N0H+1.8837NβH-0.2066NγH
By the use of the formula the chemical shifts of 99 carbon atoms are predicated, and the standard error is only 0.9861ppm. The average absolute error is 0.78ppm, The calculated values conform very much to the observed values.

Key words: Equilibrium electronegativity, Alkane, 13C NMR chemical shift

CLC Number: