Britannica
Sources used in this answer
How does NMR reveal internal magnetic fields in ferromagnets and antiferromagnets?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
magnetic resonance
Figure 1: Precession of a magnetic dipole moment μ in the presence of a constant field H and a rotating field H′ (see text)
In ferromagnets and antiferromagnets, nuclear magnetic resonance (NMR) is influenced by internal magnetic fields generated by the ordered array of electronic spins within the crystal lattice.1
These internal fields cause shifts in the NMR resonance frequency, which provide specific insights into the magnetic properties of the material:
- Ferromagnets: The observed shift in the NMR frequency serves as a direct measure of the lattice magnetization.1
- Antiferromagnets: The NMR spectrum typically exhibits at least two distinct shifts. These shifts allow for the determination of the magnetization of each antiferromagnetic sublattice separately, a level of detail that cannot be achieved through conventional magnetic measurement techniques.1
By analyzing these frequency shifts, researchers can probe the internal magnetic environment of these materials, which is made possible by the interaction between the nuclear spins and the ordered electronic magnetic moments present in the solid.1