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Updated: Aug 17, 2026

15N CPMG Relaxation Dispersion for the Investigation of Protein Conformational Dynamics on the µs-ms Timescale
Published on: April 19, 2021
Multiple refocusing in NMR spectroscopy: compensation of pulse imperfections by scalar couplings
Jens Dittmer1, Geoffrey Bodenhausen
1Institut des sciences et ingénierie chimiques, Ecole polytechnique fédérale de Lausanne, BCH, 1015 Lausanne, Switzerland. jens.dittmer@epfl.ch
Abstract:
When applying multiple refocusing pulses to characterize the cross-correlated relaxation of heteronuclear multiple quantum coherence 2NxHx in biomolecules, the unavoidable effects of pulse imperfections are compensated by the scalar couplings between nitrogen atoms and protons. The experiment, which is useful as a tool for studying slow internal dynamics of biomolecules, greatly benefits from this compensation. The underlying effect is a manifestation of an interchange between three noncommuting components of the density operator. One perturbing Hamiltonian is counteracted by another, which leads to a nearly complete suppression of the perturbation. The effect proves to be an example of a hitherto unknown phenomenon in NMR spectroscopy.
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