Solid solutions La1-xAgγMnO3+δ:: evidence for silver doping, structure and properties

Our experiments on the preparation of the composites of CMR manganites and metal silver have shown that in the case of La1-xMnO3+delta the vacancies in the A-sublattice of the perovskite structure can be filled by Ag+ ions under the soft conditions of the synthesis. Neutron diffraction refinement of La0.8Ag0.2MnO3.00 clearly proves the silver doping in the A-sublattice. Depending on P(O-2)-T synthesis conditions the solid solutions with the broad stoichiometry range La1-xAgyMnO3+delta (0.3 greater than or equal to x greater than or equal to y) were prepared. We report here the evolution of the oxygen stoichiometry, the crystal structure as well as electro-physical properties in the series of the solid solutions. Curie temperature comes over a maximum exceeding the room temperature with the increase of silver content. La1-xAgyMnO3+delta solid solutions can be useful for the construction of the room temperature magnetic field sensors based on the magnetoresi stance effect. (C) 2004 Elsevier B.V. All rights reserved.