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An overview of the role of solid-state nuclear magnetic resonance (SSNMR) spectroscopy in the field of crystal engineering is provided. NMR methodologies often provide insights into the structure and dynamics of solid materials which would otherwise be unavailable by X-ray diffraction. More generally, NMR crystallographic structure solutions or refinement approaches seek to incorporate available data from all sources, including the results of density functional theory calculations and diffraction data. This Highlight article discusses the state of the field through a recapitulation of relevant theory and selected applications from the literature. Specific topics covered include NMR structure refinement, polymorph identification and differentiation, non-covalent interactions, and the role of dynamics. [ABSTRACT FROM AUTHOR]

Halogen bonds constitute an important and topical class of non-covalent interaction. We report a combined X-ray diffraction, multinuclear (77Se, 31P, 13C) solid-state magnetic resonance, and computational study of a series of crystalline triphenylphosphine selenide-iodoperfluorobenzene complexes which feature P=Se⋯I-C halogen bonds. Selenium-77 chemical shifts increase due to halogen bonding with iodine and correlate with the P=Se distance, which in turn correlates with the strength of the halogen bond. (77Se, 31P) coupling constants increase in magnitude as the halogen bond weakens. This observation is understood a natural localized molecular orbital (NLMO) DFT approach which shows that contributions from the selenium lone pair orbital tend to dominate both the magnitude and trends in (77Se, 31P), with the selenium-phosphorus bonding orbital being the second largest contributor. This work suggests that couplings measured NMR spectroscopy may play an important role in the characterization of halogen bonds, in clear analogy with their role in the characterization of hydrogen bonds. [ABSTRACT FROM AUTHOR]