Tricritical behavior of mixed spin-2 and spin-5/2 ferrimagnetic Ising system with interlayer coupling

Tricritical points of layer Ising system consisting of mixed spin-2 and spin-5/2 ferrimagnetic honeycomb lattice layers which are coupled together with two kinds of positive interlayer coupling are examined by the use of the effective-field theory with correlations. In particular, the effects of interlayer coupling and crystal-field constants of the spin-2 ions and spin-5/2 ions on the tricritical points are investigated, in order to clarify the characteristic behavior of the first-order phase transitions and the second-order phase transitions of the system. (c) 2006 Elsevier B.V. All rights reserved.