Dynamic correlations between inhomogeneous magnetic fields, internal gradients, diffusion and transverse relaxation, as a probe for pore geometry and heterogeneity

Abstract

In this study we have applied 2D NMR experiments where the spatial inhomogeneous magnetic field (B_i) inside a porous sample is correlated to respectively internal gradient (G₀), diffusion coefficient (D), and transverse relaxation time (T₂) of a confined liquid. Experiments were performed on samples having different pore system geometry and heterogeneity, leading to different types of confinement of the liquid. The results show that the correlation between G₀ and B_i is more sensitive to the type of confinement, and thus also of the pore geometry and heterogeneity, compared to the corresponding correlations involving D and T₂.