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Nuclear magnetic resonance (NMR) crystallography-an approach to structure determination that seeks to integrate solid-state NMR spectroscopy, diffraction, and computation methods-has emerged as an effective strategy to determine structures of difficult-to-characterize materials, including zeolites and related network materials. This paper explores how far it is possible to go in determining the structure of a zeolite framework from a minimal amount of input information derived only from solid-state NMR spectroscopy. It is shown that the framework structure of the fluoride-containing and tetramethylammonium-templated octadecasil clathrasil material can be solved from the 1D 29 Si NMR spectrum and a single 2D 29 Si NMR correlation spectrum alone, without the space group and unit cell parameters normally obtained from diffraction data. The resulting NMR-solved structure is in excellent agreement with the structures determined previously by diffraction methods. It is anticipated that NMR crystallography strategies like this will be useful for structure determination of other materials, which cannot be solved from diffraction methods alone.

Room-temperature ionic liquids (RTILs) are gaining increasing interest and are considered part of the green chemistry paradigm due to their negligible vapour pressure and ease of recycling. Evidence of liquid-state order, observed by IR and Raman spectroscopy, diffraction studies, and simulated by ab initio methods, has been reported in the literature. Here, quadrupolar nuclei are used as NMR probes to extract information about the solid and possible residual order in the liquid state of RTILs. To this end, the anisotropic nature and field dependence of quadrupolar and chemical shift interactions are exploited. Relaxation time measurements and a search for residual second-order quadrupolar coupling were employed to investigate the molecular motions present in the liquid state and infer what kind of order is present. The results obtained indicate that on a timescale of approximately 10(-8) sec or longer, RTILs behave as isotropic liquids without residual order.