ABSTRACT

This chapter focuses on solid-state Nuclear magnetic resonance (NMR) of humic materials that has involved almost exclusively C NMR. Solid-state NMR has no universally-applicable spectral editing techniques that are analogous to solution methods such as off-resonance decoupling, or 2-D J-correlation. Humic materials are typically low in nitrogen content, but there may be specific cases for which this effect is significant. Rigid solids often have long longitudinal relaxation times. Both transition metal ions and organic free radicals may be found in humic samples and will be difficult to remove without changing the structure of the sample. Solid-state NMR offers a wide and expanding array of tools for characterizing the structure and dynamics of humic materials.