J. Phys. I France
Volume 4, Numéro 7, July 1994
Page(s) 1063 - 1075
DOI: 10.1051/jp1:1994184
J. Phys. I France 4 (1994) 1063-1075

Ternary coherent phase diagram on the FCC lattice

P. Cénédèse1, Y. Calvayrac1 and A. Marty2

1  CECM/CNRS, 15 rue G. Urbain, 94407 Vitry-sur-Seine, France
2  CENG/DRFMC/SPMM/MP, 85X, 38041 Grenoble Cedex, France

(Received 28 January 1994, received in final form 25 March 1994, accepted 30 March 1994)

In this paper, we describe a general and original method to study the ground state problem, in multicomponent systems. The method is illustrated by considering the nearest neighbour Ising model in ternary FCC lattices, and leads to the occurrence as a ground state of a new phase called L'. The ternary coherent phase diagram is then calculated within the CVM tetrahedron approximation, showing Chat the L' phase displays a stability domain as large as those of the L1 0 and L1 2 domains. At low but non-zero temperature, a "quaternary ground state" phase, called L", stabilized by entropy effects, appears in the phase diagram.

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