Rapidly Screening the Correlation between the Rotational Mobility and the Hydrogen Bonding Strength of Confined Water.

Automated Deuterium Relaxation-Ordered SpectroscopY in solution (ADROSYS), an automated two-dimensional deuterium NMR methodology, discriminates between DO populations (as well as deuterium-labeled alcohol groups) whose properties differ as a result of being confined inside nanoscale volumes. In this contribution, a proof-of-principle demonstration on reverse micelles (RMs) yields the insight that as the length scale of the confinement decreases from several nanometers down to less than a nanometer, the position of the signal peak migrates through the two-dimensional (2D) spectrum, tracing out a distinctive path in the 2D space (of relaxation time vs chemical shift). The signals typically follow a relatively gentle linear path for water confined on the scale of several nanometers, before curving once the surfactants confine the water molecules to length scales smaller than 1-2 nm.

A modernized view of coherence pathways applied to magnetic resonance experiments in unstable, inhomogeneous fields.

This article presents a standardized alternative to the traditional phase cycling approach employed by the overwhelming majority of contemporary Nuclear Magnetic Resonance (NMR) research. On well-tested, stable NMR systems running well-tested pulse sequences in highly optimized, homogeneous magnetic fields, the hardware and/or software responsible for traditional phase cycling quickly isolate a meaningful subset of data by averaging and discarding between 3/4 and 127/128 of the digitized data. In contrast, the new domain colored coherence transfer (DCCT) approach enables the use of all the information acquired from all transients.