THE REMANENT STATE OF FINE PARTICLES

Computations of the structure and energy of the magnetization configurations in very small particles have reached the limit of validity of the basic assumptions used in this theory, and the analytic models which have been published so far are not more reliable, for anything but ellipsoids. A review of all the theoretical studies leads to the conclusion that a good and clear definition of what fine particles really are should be introduced before trying to evaluate their magnetization.