Question

What is antiferromagnetic material?

Answer 1

1. When any material is placed in an applied magnetic field, it experiences the field and thus induces a magnetic property in it.
2. These magnetic properties are induced on the macroscopic level based on the interaction between the individual dipole moments of an atom with the applied magnetic fields.
3. The one that shows the commonly known property that the material is attracted to the magnetic field wholly, is known as the ferromagnet. In this, the magnetic moments of each atom are all aligned in the same direction.
4. In the case of antiferromagnets, the magnetic moments of each atom are arranged in such a way that every second moment is in the opposite direction to the first.
5. In simple words, in a pair of atoms, the moments are arranged in such a way that they cancel out each other. That is if one is upwards the other will be downwards.
6. Thus, in anti-ferromagnets, the net magnetic moment of the substance is zero as the alternate orientations of moment cancel out each other. This indicates that they do not produce any magnetic field of their own.
7. The anti-ferromagnetic nature can be destroyed by heating at higher temperatures.
8. Examples are Manganese oxide, $\left(\mathrm{MnO}\right)$, Chromium oxide, $\left({\mathrm{Cr}}_2{\mathrm{O}}_3\right)$, Ferrous oxide $\left(\mathrm{FeO}\right)$ etc.