NMR diffusometry and the short gradient pulse limit approximation
Author
Summary, in English
In NMR diffusometry, one often uses the short gradient pulse (SGP) limit approximation in the interpretation of data from systems with restricted diffusion. The SGP limit approximation means that the gradient pulse length, delta, is so short that the spins do not diffuse during the pulse duration, but this condition is rarely met. If the length scale of the pores corresponds to the molecular mean square displacement during the gradient pulse, the measured echo intensities become a function of the gradient pulse length. Here, we have studied highly concentrated emulsions to show how the length of the gradient pulse influences NMR diffusion experiments. We have focused on molecules confined to one pore and molecules that can migrate through the porous system. For the former the echo decays give smaller pores than the actual case and for the latter we show large changes in echo decay depending on the gradient pulse length, everything else being equal. (C) 2004 Elsevier Inc. All rights reserved.
Department/s
Publishing year
2004
Language
English
Pages
85-91
Publication/Series
Journal of Magnetic Resonance
Volume
169
Issue
1
Document type
Journal article
Publisher
Academic Press
Topic
- Physical Chemistry
Keywords
- NMR
- Diffusometry
- SGP
- Short gradient pulse limit approximation
- Restricted diffusion
- Concentrated emulsions
Status
Published
ISBN/ISSN/Other
- ISSN: 1096-0856