Size Dependence of the Wall Characteristics in a Two-Domain Iron Particle

The study of the energy per unit volume versus wall width in a cubic two-domain iron particle leads to the following results: (1) The width and energy per unit area of the wall have values considerably different from their values in bulk iron. (2) The width of the wall slowly rises with increasing size of the cube while the energy decreases. (3) The two-domain configuration is energetically unstable when the cube edge is less than 200 A, in fair agreement with current single domain criteria.