Every substance has some magnetic properties associated with it. The origin of these properties lies in the electrons. Each electron in an atom behaves like a tiny magnet. Its magnetic moment originates from two types of motions.

(i) Its orbital motion around the nucleus and

(ii) Its spin around its own axis.

Electron being a charged particle and undergoing these motions can be considered as a small loop of current which possesses a magnetic moment. Thus, each electron has a permanent spin and an orbital magnetic moment associated with it. Magnitude of this magnetic moment is very small and is measured in the unit called Bohr magneton, µB. It is equal to 9.27 × 10^–24 Am². On the basis of their magnetic properties, substances can be classified into five categories:

(i) Paramagnetic

(ii) Diamagnetic

(iii) Ferromagnetic

(iv) Antiferromagnetic and

(v) Ferrimagnetic.

Which of the following substances have domain structure similar to ferromagnetic substances?

Antiferromagnetic

The correct answer is option 2. Antiferromagnetic.

Antiferromagnetism: Substances like MnO showing anti-ferromagnetism have domain structure similar to ferromagnetic substance, but their domains are oppositely oriented and cancel out each other's magnetic moment.