A new method for measuring diffusion coefficients by 2D NMR using accordion spectroscopy

Translational diffusion measurements are a useful tool for studying supramolecular complexes and for characterizing the association state of molecules that aggregate at NMR concentrations. Pulsed field gradients can be used to measure diffusion coefficients. Spectral overlap problems in complex mixtures can be alleviated by using 2D spectroscopy but the need to record a complete series of 2D spectra with increasing gradient strength makes these experiments extremely time consuming. Concerted incrementation of the gradient strength and the evolution time provides a new version of accordion spectroscopy that allows the measurement of individual diffusion coefficients in complex mixtures in a single experiment. Copyright 1998 Academic Press.