Blume-Emery-Griffiths model

Hoston W, Berker AN. Multicritical phase diagrams of the Blume-Emery-Griffiths model with repulsive biquadratic coupling. Physical Review Letters. 1991 67 1027-1030. DOI 10.1103/PhysRevLett.67.1027. 

The Blume-Emery-Griffiths (BEG) model is one of the well-known spin lattice models in equilibrium statistical mechanics. It was originally introduced with the aim to account for phase separation in helium mixtures [30]. Besides various thermodynamic properties, the model has been extended to study the structural phase transitions in many bulk systems. By... 

Berker AN, Wortis M. Blume-Emery-Griffiths-Potts model in two dimensions phase diagram and critical properties from a position-space renormalization group. Physical Review B. 1976 14 4946-4963. DOI 10.1103/PhysRevB.14.4946. 

This Blume-Emery-Griffiths (BEG) model [74] has been studied both by mean field calculations as well as by simulations. There is no pronounced difference between the amphiphile molecules 5 = 0, the oil or the water. Indeed, the model was first suggested in a quite different context. An extension of the model by Schick and Shih [75] includes an additional interaction of the form... 

Emery-Griffiths model (BEG) (Blume et at, 1971). Recently, there have been many theoretical studies of mixed spin Ising systems. These are of interest because they have less translational symmetry than their single-spin counterparts since they consist of two interpenetrating inequivalent sublattices. The latter property is very important to study a certain type of ferrimagnetism, namely molecular-based magnetic materials which are of current interest (Kaneyoshi Nakamura, 1998). 

These unusual pseudobinary phase diagrams were derived initially by Meijering (1950) from a simple mixture model for ternary mixtures. Much later, Blume, Emery and Griffiths (1971) deduced the same diagrams from a three-spin model of helium mixtures. The third diagram on the right of figure A2.5.30 is essentially that found experimentally for the fluid mixture He+ He the dashed line (second-order transition) is that of the A,-transition. 

Blume M, Emery VJ, Griffiths RB. Ising model for the A transition and phase separation in He3-He4 mixtures. Physical Review A. 1971 4 1071-1077. DOI 10.1103/Phys-RevA.4.1071. 

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