Monte Carlo Study of an Ordering Alloy on an fcc Lattice

Abstract

We report results of computer simulations of a binary alloy on an fcc lattice, equivalent to an Ising system with a nearest-neighbor antiferromagnetic interaction $J>\mathrm{}0\mathrm{}$ and a next-nearest-neighbor ferromagnetic interaction $-\alpha J$, $\alpha >0\mathrm{}$. Our data indicate the existence of a discontinous change in energy and in sublattice magnetization as a function of temperature, for small $\alpha$. For $\alpha \gtrsim 0.25$, the transition appears to be continuous, suggesting a tricritical point at some intermediate $\alpha$.