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Updated: May 25, 2026

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
Coupling between internal dynamics and rotational diffusion in the presence of exchange between discrete molecular
Yaroslav Ryabov1, G Marius Clore, Charles D Schwieters
1Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Building 12A, Bethesda, Maryland 20892-5624, USA.
Abstract:
We present a general formalism for the computation of orientation correlation functions involving a molecular system undergoing rotational diffusion in the presence of transitions between discrete conformational states. In this formalism, there are no proscriptions on the time scales of conformational rearrangement relative to that for rotational diffusion, and the rotational diffusion tensors of the different states can be completely arbitrary. Although closed-form results are limited to the frequency domain, this is generally useful for many spectroscopic observables as the result allows the computation of the spectral density function. We specialize the results for the computation of the frequency-domain correlation function associated with the NMR relaxation.
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