A New Correlation of 1 J (C13,H) and Carbon Atom Orbital s Character Useful for Mapping s Character Frameworks in Molecules and Estimating Bond Angles: Fluorine‐Substituent Effects on 1 J (C13,H)

Previous NMR 1 J (C13,H) –s correlations exhibited only marginal degrees of success. Presented here is a new such correlation where it is proposed NMR coupling data is passed by H–C–H and H–H pathways as suggested by the theoretical results of Provasi et al. Used where the current best values of the 1 J (C13,H)'s and molecular structure data for the hydrocarbons methane ( 1 ), ethane ( 2 ), ethene ( 3 ), benzene ( 4 ), propadiene ( 5 ), and ethyne ( 6 ). Simple equations for calculation of s character and bond angles are presented. The correlation has been extended to the case of a fluorine substituent. How the s character frameworks of molecules can be mapped out is demonstrated and compared to natural bond orbital (NBO) analysis estimations from density functional theory calculations. The definitions and calculation of the parameters in the master equation, 1 J (C13,H) = A s + n B + m C + o D + E + F , are explained in detail.