Editing Antiferromagnetism (section)

== Measurement ==
When no external field is applied, the antiferromagnetic structure corresponds to a vanishing total magnetization. In an external magnetic field, a kind of ferrimagnetic behavior may be displayed in the antiferromagnetic phase, with the absolute value of one of the sublattice magnetizations differing from that of the other sublattice, resulting in a nonzero net magnetization. Although the net magnetization should be zero at a temperature of [[absolute zero]], the effect of [[spin canting]] often causes a small net magnetization to develop, as seen for example in [[hematite]].<ref>{{Cite book |last=Coey |first=J. M. D |title=Magnetism and Magnetic Materials |publisher=Cambridge University Press |year=2009 |isbn=978-0-521-81614-4 |location=Cambridge |pages=196}}</ref>

The [[magnetic susceptibility]] of an antiferromagnetic material typically shows a maximum at the Néel temperature. In contrast, at the transition between the ferromagnetic to the paramagnetic phases the susceptibility will diverge. In the antiferromagnetic case, a divergence is observed in the ''staggered susceptibility''.

Various microscopic (exchange) interactions between the magnetic moments or spins may lead to antiferromagnetic structures. In the simplest case, one may consider an [[Ising model]] on a [[:wikt:bipartite|bipartite]] lattice, e.g. the simple [[cubic crystal system|cubic lattice]], with couplings between spins at nearest neighbor sites. Depending on the sign of that interaction, ferromagnetic or antiferromagnetic order will result. [[Geometrical frustration]] or [[ANNNI model|competing]] ferro- and antiferromagnetic interactions may lead to different and, perhaps, more complicated magnetic structures.

The relationship between [[magnetization]] and the [[magnetizing field]] is [[linear relation|non-linear]] like in [[Magnetic susceptibility#Differential susceptibility|ferromagnetic materials]]. This fact is due to the contribution of the [[hysteresis loop]],<ref>{{cite journal|first1=Hrouda|last1= František|title=Low-field variation of magnetic susceptibility and its effect on the anisotropy of magnetic susceptibility of rocks|journal=Geophysical Journal International|volume =150|issue= 3|date= September 1, 2002|pages= 715–723|issn=1365-246X|publisher=Oxford University Press|doi= 10.1046/j.1365-246X.2002.01731.x|bibcode= 2002GeoJI.150..715H|oclc=198890763|doi-access=free}}</ref> which for ferromagnetic materials involves a [[residual magnetization]].