NMR-Based Diffusion Lattice Imaging

TL;DR

This paper demonstrates that NMR diffusion experiments, specifically using the SERPENT sequence, can fully reveal the structure of periodic open systems by analyzing diffusion data with an iterative Gaussian envelope model.

Contribution

It introduces a theoretical approach showing that open system structures can be fully reconstructed from NMR diffusion data using the SERPENT sequence and an iterative Gaussian model.

Findings

Full structural information of periodic open systems is accessible.

The method applies to lattices of cylinders and triangles.

Diffusion data can be used to determine open system geometries.

Abstract

Nuclear magnetic resonance (NMR) diffusion experiments are widely employed as they yield information about structures hindering the diffusion process, e.g. about cell membranes. While it has been shown in recent articles, that these experiments can be used to determine the exact shape of closed pores averaged over a volume of interest, it is still an open question how much information can be gained in open systems. In this theoretical work, we show that the full structure information of periodic open systems is accessible. To this end, the so-called 'SEquential Rephasing by Pulsed field-gradient Encoding N Time-intervals' (SERPENT) sequence is used, which employs several diffusion weighting gradient pulses with different amplitudes. The structural information is obtained by an iterative technique relying on a Gaussian envelope model of the diffusion propagator. Two solid matrices that are surrounded by an NMR-visible medium are considered: a hexagonal lattice of cylinders and a cubic lattice of triangles.