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How does ferrimagnetism create a net magnetic field?

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Learn about magnetic fields and the levels of particles, atoms, crystals, and domains — magnet Magnetic fields and the levels of magnetism of particles, atoms, crystals, and domains.

Ferrimagnetism creates a net magnetic field through the spontaneous alignment of atomic magnetic dipoles in a specific, ordered structure. Unlike ferromagnetism, where all dipoles align in the same direction, ferrimagnetic materials contain two or more sublattices with magnetic moments that align in opposite, or antiparallel, directions.123

The emergence of a net magnetic field occurs because these opposing sublattices possess unequal magnetic moments. Because the moments are not of equal magnitude, they do not cancel each other out completely as they would in an antiferromagnetic material. Instead, the smaller moments are subtracted from the larger ones, resulting in a resultant net magnetization that is parallel to the direction of the sublattice with the larger moment.13

A classic example is magnetite (Fe $_{3}$ O $_{4}$ ), a ferrite where iron ions are arranged in these unequal sublattices. While the iron(III) ions may be paired off in opposite directions, the iron(II) ions align in a way that accounts for the material's observable external magnetic field. This spontaneous alignment persists below the material's Curie point.123