Steady state effects in PGSE NMR diffusion experiments

To increase the speed of diffusion measurements the Hahn spin-echo based PGSE sequence can be altered by the addition of a crusher gradient pulse during the prescan delay (SS-PGSE) and the recycle delay reduced. The measured diffusion coefficients (D) diverge when the prescan delay approaches the longitudinal relaxation time constant (T1) in disagreement with theory.