Numerical analysis of NMR diffusion experiments in complex systems

The pulsed gradient spin-echo (PGSE) nuclear magnetic resonance experiment is now a formidable tool for probing porous media through geometry-dependent diffusive diffraction effects. However, for anything but relatively simple geometries numerical approaches must be used to model and interpret the experimental results. Here a simple, powerful, flexible and computationally efficient finite element method approach is developed and demonstrated. The results show that this new approach has great potential for modelling the results of PGSE experiments on real porous systems. The study of porous media is vital to our continued understanding of physical systems, and further development of analysis techniques. Porous media can be on the nanometre scale, such as liquid crystal aggregates, to the 10-100 µm scale for systems such as human brain cells and porous rock.