In materials that exhibit
antiferromagnetism, the
magnetic moments of
atoms or
molecules, usually related to the spins of
electrons, align in a regular pattern with neighboring
spins (on different sublattices) pointing in opposite directions. This is, like
ferromagnetism and
ferrimagnetism, a manifestation of ordered
magnetism. Generally, antiferromagnetic order may exist at sufficiently low temperatures, vanishing at and above a certain temperature, the
Néel temperature (named after
Louis Néel, who had first identified this type of magnetic ordering). Above the Néel temperature, the material is typically
paramagnetic.