Magnetic study of interatomic interactions, synthesis, structural and mass spectroscopy investigations of lanthanum gallate doped with cobalt and magnesium

• Single phase LaCoxGa1−1.2xMg0.2xO3 and LaCoxGa1−1.5xMg0.5xO3 solutions were obtained.
• Two crystalline modifications of solid solutions were found by Rietveld method.
• Ferromagnetic clusters including Co, Mg and accompanying oxygen vacancies are found.
• Magnetic behavior of clusters is of superparamagnetic type.

For the first time by X-ray method two phases of the solid solutions LaCoxGa1−1.2xMg0.2xO3−δ and LaCoxGa1−1.5xMg0.5xO3−δ (x = 0.01–0.10) with different structure were found – rhombohedral and orthorhombic phases. On the basis of the data on evaporation of the components a synthetic procedure was advanced allowing the losses of cobalt to be minimized. The study of magnetic characteristics of obtained solid solutions showed the formation of high nuclearity clusters containing cobalt atoms, and also magnesium and associated vacancies even in diluted solid solutions. Clusters are characterized by a competition between ferro- and antiferromagnetic exchange interactions, whereas the long order exchange is antiferromagnetic.