Antiferromagnetism

Antiferromagnetism arises from the same phenomena as ferromagnetism and is a result of the atoms or molecules aligning with each other due to their electron spins. However, they align so that their fields are in opposition. Antimagnetic characteristics are usually present at relatively low temperatures but on raising the temperature they disappear at a given temperature called the Néel temperature. Above this temperature the material becomes paramagnetic in character. Examples of antiferromagnetic materials are chromium, iron-manganese alloy, nickel oxide and haematite.