NMR Splittings Due to Molecular Asymmetry

Abstract

An algebraic analysis is given of the relative effects of molecular asymmetry and differences in conformational populations in causing nuclei to be magnetically nonequivalent. Primary importance is attached to the nature of the molecular asymmetry. The temperature dependence of the chemical shift observed between F_a and F_b, in CF_aF_bBrCFBrCl, is compatable with a small splitting, an ``asymmetry effect,'' which persists when the three rotamers have the same population.