Self-diffusion coefficients (D) are measured by recording a series of NMR experiments in which the overall gradient strength (G) is progresively incremented in each experiment. The attenuated NMR signal (A) follows this equation:
When data is plotted accordingly to
the slope of the resulting line affords the D value.
As a rough approximation, the measured diffusion coefficient is related to the hydrodynamic radius using the Stokes-Einstein equation: