Skin, soap, and spaghetti: investigations of co-existing solid and liquid phases in organic materials using solid-state NMR with dynamics-based spectral editing
Daniel Topgaard
Abstract
Abstract Solid-state NMR methods incorporating dynamics-based spectral editing have a remarkable versatility for resolving and separately characterizing co-existing solid and liquid phases or domains in biologically and technically relevant organic materials. While 13 C spectra acquired under magic-angle spinning and 1 H decoupling provide atomic resolution, the signal intensities obtained with the CP and INEPT polarization transfer techniques give qualitative information about dynamics. This mini-review covers the basics of translational and rotational motion of atoms and molecules in organic materials, theoretical aspects of the relations between C–H bond reorientation and CP and INEPT signal intensities, and applications of the methods to a broad range of heterogeneous materials comprising hydrated assemblies of surfactants, lipids, proteins, and/or carbohydrates.