From molecular view point, discuss the temperature dependence of susceptibility for diamagnetism, paramagnetism and ferromagnetism.

Explanation

Orbital motion of electrons causes diamagnetism. Electrons in an atom orbiting around nucleus possess orbital magnetic moment. When magnetic field is in the same direction slow down and those in the opposite direction speed up. Thus, the net magnetic moment is developed opposite to the applied field and is nearly independent of the internal motion of electrons (which is affected by temperature). So, susceptibility for diamagnetism is independent of temperature. Paramagnetism and ferromagnetism arise due to alignment of atomic magnetic moments in the direction of applied field. On increasing the temperature, the alignment of dipoles gets disturbed due to thermal agitation. Thus, susceptibility for both paramagnetism and ferromagnetism decreases with increase in temperature.