We study the spin-1 Blume–Capel model under a random crystal field in the tridimensional semi-infinite case. This has been done by using the real-space renormalization group approximation and specifically the Migdal–Kadanoff technique. Interesting results are obtained, which tell us that the...

The random-crystal field spin-1 Blume–Capel model is investigated by the lowest approximation of the cluster-variation method which is identical to the mean-field approximation. The crystal field is either turned on randomly with probability p or turned off with q=1−p in a bimodal...

The bond dilution Blume–Capel model with random crystal field is considered in the framework of the effective field theory. The expressions of magnetizations for honeycomb and square lattices are derived. Special emphasis is placed on thermodynamic properties of the two lattices and the...

We study the phase diagram of the mean-field spin-1 Ising ferromagnet in a uniform magnetic field H and a random crystal field Δi, with probability distribution P(Δi) = pδ(Δi −Δ) + (1 − p)δ(Δi). We analyse the effects of randomness on the first-order surfaces of the Δ−T−H phase...

In the presence of quenched random crystal fields, phase transitions in magnetic thin films described by the spin-1 Blume–Capel model have been investigated using effective field theory (EFT). Crystal field disorder has been sampled by introducing dilute and trimodal random crystal fields. For...

The dependence of the phase diagrams on the random crystal field (RCF) is investigated for the spin-1 Blume–Capel (BC) model on the Bethe lattice. The calculations are carried out in terms of the recursion relations for the coordination number z=4 which corresponds to the square lattice. The...

The critical properties of the mixed-spin Ising model consisting of spin- 1/2 and 3/2 are investigated in the presence of a bimodal random crystal field by using the effective field theory with correlations. The thermal variations of magnetizations are studied in detail to obtain the phase...