A Weiss-type model of ferromagnetism

The classical Weiss model of ferromagnetism is extended to nonuniform systems, by assuming the molecular field to be proportional to the convolution of the magnetization field with a nonnegative (e.g. Gaussian) kernel. Dealing with processes, a dynamic term accounting for dry friction-like dissipation due to wall pinning is also included in the constitutive equation. These models are mathematically well-behaved when coupled either with the magnetostatic equations or with Maxwell's equations. A similar modification is introduced for antiferromagnetism and ferrimagnetism. (C) 2000 Elsevier Science B.V. All rights reserved.