Abstract: The linear relationship between one bond carbon-hydrogen spin-spin coupling constants J_CHand the sum of internuclear angle distortions ∑_△θ or that of real bond angle dissortion∑_△βhas been found.Quadratic expressions of J_CH vs.θ_CCC and J_CH vs.s%(C—H) are obtained by fitting polynomials to experimental coupling constants J_CH andθ_CCC or s%(C—H) bonds for the type R₂CH₂.All the proposed formulae give J_CHvalues with less than 2.0 Hz average deviations from experimental values.

Key words: Coupling constants of ¹³C—H, Ringed organic molecules, Bond angle distortions