Possible types of ordering cation vacancies in structures of the NiAs type

A connection was found between the type of vacancy distribution and the magnetic properties of non-stoichiometric ferrimagnets such as pyrrhotite. Within the framework of the molecular-field approximation, a theoretical explanation was given to the dependence of the magnetization on the temperature of magnetically ordered compounds containing cation vacancies in the crystal structure. On the basis of the proposed model of the vacancy behavior, the theoretically possible dependences of the magnetization on the temperature were presented.