Chapter 4: Two-dimensional Methods for Half-integer Quadrupolar Nuclei Check Access

In the present chapter, we review some of the most robust and commonly used two-dimensional (2D) solid-state NMR experiments for half-integer spin quadrupolar nuclei. It covers techniques from high-resolution methods, such as Multiple-Quantum Magic-Angle Spinning (MQMAS) or Satellite Transition Magic-Angle Spinning (STMAS), to recent developments of homo- and hetero-nuclear correlation sequences, for the latter with a focus on the most efficient recoupling schemes. For each sequence, strategies for quick and easy experimental optimisation are detailed. Then, the information that can be deduced from the spectra is illustrated by a few recent and complementary examples dealing with inorganic systems, from ordered to partially or totally disordered structures.