Multiple Acquisition Strategies

Methodology advancements in NMR spectroscopy are typically classified as those involving improvements in sensitivity or resolution. This chapter focuses on the detection of two or more free induction decays during a single experiment, referred to as multiple acquisitions. Collection of multidimensional experiments requires establishing correlations to link spin systems for resonance assignments. During the process of selecting the desired coherence for spectral acquisition, unwanted coherences are often created and typically discarded using phase cycling and pulsed field gradients. A wide range of experiments have been developed that implement multiple acquisition periods in both solution and solid-state NMR spectroscopy. The chapter presents examples of such methods grouped by sample type in the form of solution or solid-state NMR applications with a focus on biomolecular NMR applications. The multiple acquisition methods increase the effective sensitivity of NMR data collection since the additional spectra do not increase the overall experimental acquisition time.