Manganese tetraoxide is ferrimagnetic at low temperatures and paramagnetic at room temperature
The magnetic properties of manganese tetraoxide (Mn₃O₄) are closely related to temperature, and can be divided into the following two situations:
Ferrimagnetism at low temperatures
When the temperature is lower than 41-43K (about -232℃ to -230℃), manganese tetraoxide exhibits ferrimagnetism (a special ferromagnetic ordered state). This property originates from the antiparallel arrangement of divalent manganese ions (Mn²⁺) and trivalent manganese ions (Mn³⁺) in the lattice in its spinel structure, resulting in a non-zero net magnetic moment.
Paramagnetic properties at room temperature
At room temperature (about 300K), manganese tetraoxide exhibits paramagnetism, that is, it will be weakly attracted in an external magnetic field, but will not retain magnetism after the magnetic field is removed. This property is related to the thermal perturbation of its electron spins.
