Spectral Editing in 13C MAS NMR under Moderately Fast Spinning Conditions
Authors: de Vita, E.; Frydman, L.
Source: Journal of Magnetic Resonance, Volume 148, Number 2, February 2001 , pp. 327-337(11)
Publisher: Academic Press
Abstract:Novel procedures for the spectral assignment of peaks in high-resolution solid-state 13C NMR are discussed and demonstrated. These methods are based on the observation that at moderate and already widely available rates of magic-angle spinning (10–14 kHz MAS), CH and CH2 moieties behave to a large extent as if they were effectively isolated from the surrounding proton reservoir. Dipolar-based analogs of editing techniques that are commonly used in liquid-state NMR such as APT and INEPT can then be derived, while avoiding the need for periods of homonuclear 1H–1H multipulse decoupling. The resulting experiments end up being very simple, essentially tuning-free, and capable of establishing unambiguous distinctions among CH, CH2, and carbon sites. The principles underlying such sequences were explored using both numerical calculations and experimental measurements, and once validated their editing applications were illustrated on a number of compounds.
Document Type: Research Article
Affiliations: Department of Chemistry (M/C 111), University of Illinois at Chicago, 845 W. Taylor Street, Chicago, Illinois, 60607-7061
Publication date: February 1, 2001