Mössbauer and other studies establish that in ${\mathrm{La}}_{1-x}{\mathrm{Sr}}_x\mathrm{Co}{\mathrm{O}}_3$ ($x>\mathrm{}0.125\mathrm{}$), ferromagnetic ${\mathrm{Sr}}^{2+}$ -rich clusters coexist with paramagnetic ${\mathrm{La}}^{3+}$ -rich regions in the same crystallographic phase, with the ferromagnetic component increasing with increasing $x$ and decreasing $T$. The $3d$ holes created by ${\mathrm{Sr}}^{2+}$ substitution are itinerant both above and below $T_C$. All the experimental observations on this system can be explained on the basis of itinerant-electron ferromagnetism.

• Received 25 June 1974

DOI:https://doi.org/10.1103/PhysRevB.12.2832