Using the methods of X-ray diffraction analysis, X-ray spectroscopy and theoretical physics, we studied the patterns of changes in the atomic, electronic and magnetic subsystems in ferrites of variable composition MnxZnyFezO4 associated with the formation of clusters differing in the composition of cations. Experimentally detected clusters, which appear in X-ray diffraction patterns as a halo, are characterized by a certain superposition of ion states, the magnetic moment of which depends not only on the spin of the electron, but also on its orbital moment and the spin of the nucleus. A phase transition was discovered in the mesoscopic cluster structure from manganese-containing clusters, caused by the interaction of trivalent manganese ions with oxygen ions, to clusters with a predominance of di- and trivalent manganese ions with oxygen ions. It is found that the clustered structure of manganese-zinc ferrites is responsible for the appearance of extreme magnetic properties; the maximum corresponds to a change in the dominant type of clusters. It is found that with an increase in mass density, a repopulation of energy states occurs as a decrease in the states of the low-energy electron group and an increase in the high-energy Fermi surface in the form of a saddle. It has been established that the peculiarities of condensation of the fundamental and soft modes of complexes (clusters) containing manganese and oxygen ions lead to changes in the physical parameters of the samples.