Improved methods for assignment of multiplicity in ¹³C NMR spectroscopy with application to the analysis of mixtures

Abstract

Abstract Improved methods for the assignment of resonance multiplicity in 13 C NMR spectra are described. Assignments are achieved either by direct observation of resonance intensity modulations resulting from gated spin echo (GASPE) experiments, or from the derivation of ‘selected multiplet’ spectra containing only C, CH, CH 2 or CH 3 carbon resonances. The methods are time‐efficient and, by comparison with the single frequency off‐resonance decoupling assignment technique, show improved spectral resolution. Chemical mixtures are used to illustrate the procedures. Possible application to materials deriving from fossil fuel sources is considered.