High-Resolution NMR in Magnetic Fields with Unknown Spatiotemporal Variations

Abstract

NMR Under Stormy Conditions Nuclear magnetic resonance spectroscopy is immensely useful for molecular characterization. However, the resolution necessary for making fine structural distinctions relies on sample isolation in a surrounding magnetic field that exhibits minimal variation in space and time over the course of the measurement; this requirement limits the range of materials that can be easily probed. Pelupessy et al. (p. 1693 ) present an approach that circumvents the need for spatiotemporal field homogeneity by detecting coherence transfer among coupled spins. Whereas prior methods have compensated for heterogeneity by applying corrective magnetic fields, this technique relies on the inherent insensitivity of the measured coherences to changes in the local magnetic environment and thus can be applied without prior knowledge of the field variation profile.