Abstract

A previously proposed model, based on the attractor role of doping cations, is extended to account for the electric and magnetic behavior on La_1-xCa_xMnO₃ manganites in the whole compositional range (0 < x < 1). From this model, the spontaneous magnetization value is predicted quantitatively over the entire compositional range of the solid solution. By further including as basic parameters the tolerance factor and the band-width, the model is expanded to give an overall description of other Ln_1-xT_xMnO₃ systems (Ln = lanthanide, T = alkaline-earth metal) with special emphasis in explaining the asymmetry and complexity of the magnetic phase diagrams. Those basic parameters are accounted for, in turn, by compositional variations, x, as well as by effects due to the different size of substitutional atoms. The model also sheds some light on the current issue of explaining the phase segregation and allowing the prediction of the spontaneous magnetization values in Ln_1-xT_xMnO₃ systems.