Explicit calculation of nuclear magnetic resonance relaxation rates in small pores to elucidate molecular scale fluid dynamics

TL;DR

This paper introduces a model that connects molecular-scale fluid dynamics in nano-pores to NMR relaxation rates, providing insights into diffusion mechanisms and pore structures in porous materials.

Contribution

The paper presents a novel model linking nano-scale fluid dynamics to NMR relaxation rates, incorporating Levy statistics and fitting experimental data for water and oil in shale.

Findings

Consistent intra-pore dynamical time constants identified

Enhanced understanding of diffusion mechanisms in nano-pores

Model applicable to various porous systems

Abstract

A model linking the molecular-scale dynamics of fluids confined to nano-pores to nuclear magnetic resonance (NMR) relaxation rates is proposed. The model is fit to experimental NMR dispersions for water and oil in an oil shale assuming that each fluid is characterised by three time constants and L\'{e}vy statistics. Results yield meaningful and consistent intra-pore dynamical time constants, insight into diffusion mechanisms and pore morphology. The model is applicable to a wide range of porous systems and advances NMR dispersion as a powerful tool for measuring nano-porous fluid properties.