Theoretical evidence for the presence of "spin-liquid" like phase in frustrated ferrimagnetic J 1 − J 2 systems on body-centered cubic lattice

Highlights: • Ferrimagnetic mixed spin systems on body-centered cubic recursive lattice are studied exactly. • The existence of new intermediate phase is predicted in all investigated models. • The second-order nature of all phase transitions is shown and all phase diagrams are found. • All possible series of consecutive phase transitions are identified and discussed. • Magnetization properties of all phases of studied models are investigated in detail. Using the recursive lattice technique the existence of the intermediate phase, which separates two ferrimagnetic phases in the $1/2-\sigma$ ($\sigma =1,3/2,2$) mixed-spin Ising ferrimagnets with the presence of the next-to-nearest neighbor interaction on the regular body-centered cubic lattice, is predicted. It is shown that, for given spin value of the central sites of the body-centered cubic lattice, this intermediate phase is realized in the corresponding narrow interval of the values of the frustration parameter of the model, that the form of the region, where the intermediate phase exists, depends on the value of the central spin σ (becomes larger with increasing of σ), and that all transitions between various phases of the model always have the second order nature. All possible series of consecutive phase transitions of the model are identified and the properties of the sublattice magnetizations are studied and discussed in detail.