Magnetic Properties of a Mixed Spin-2 and Spin-5/2 Heisenberg Ferrimagnetic System on a Two-Dimensional Honeycomb Lattice: Green's Function Approach

<正> The multisublattice Green's function technique is applied to study the magnetic properties of a mixedspin-2 and spin-5/2 Heisenberg ferrimagnetic system on a two-dimensional honeycomb lattice.The role of the differentinteractions in the Hamiltonian is explored.When only the nearest-neighbor interaction and the single-ion anisotropy areincluded,our results indicate that there are compensation points at finite temperatures.When the next-nearest-neighborinteraction exceeds a minimum value that depends on the other parameters in the Hamiltonian,the compensation pointdisappears.The next-nearest-neighbor interaction has the effect of changing the compensation temperature.