Phase diagrams of the spin (3/2, 2) Ising system on two-layer square lattice in (T, h) plane for the FM/FM interactions (J₁ > 0 and J₂ > 0), J₁ = 1.0 and J₂ = 1.0. The solid and dashed lines are the second- and first-order lines, respectively. TR, B, TP and QP represent thedynamic tricritical, dynamic critical end, triple and quadruple points, respectively. (a) J₃ = 5, D_A = 0.0 and D_B = 0.0, (b) J₃ = 0.25, D_A = − 0.5, D_B = 0.0; (c) J₃ = 5, D_A = 0.0, D_B = −0.55, (d) J₃ = 0.25, D_A = −0.5, D_B = −0.25, (e) J₃ = 5, D_A = −0.25, and D_B = −0.5, (f) J₃ = 0.25, D_A = −0.25, and D_B = −0.5.