Ferrimagnetism and defect clusters in Fe(1-x)Ofilms

Nonstoichiometric single phase Fe1-xO films with ferrimagnetic properties, large saturation magnetization (M-s), and low-temperature coercivity (H-c) have been prepared and studied. A model on the relation between M-s and the lattice parameter (a) is proposed. The model is based on the existence of 16:5 spinel-type defect clusters, and predicts a linear dependence between M-s and a. The experimental data of M-s versus a is a straight line passing through the point (M-s,a) of bulk Fe3O4. This fact suggests that Fe1-xO is the link between the two phases Fe3O4 and FeO, which have seemingly differ ent physical nature and properties, into one class of materials. [S0163-182 9(99)08221-1].