Neutron Powder Diffraction Study in La0.85Ag0.15MnO3

Abstract

La0.85Ag0.15MnO3, the colossal magnetoresistance compound was prepared and the neutron powder diffraction patterns at different temperatures down to 19 K were recorded to study their crystal structure and magnetic properties. These patterns were analyzed by the Rietveld refinement technique and are found to be free from any impurity phase. The compound is found to crystallize in a mixture of \(R\overline{3}c\) and Pnma space group and the phase fraction is found to vary with temperature. A cross-over from \(R\overline{3}c\) dominated high temperature phase to Pnma dominated low temperature phase at around 130 K was observed. At low temperatures, especially below 285 K, the diffraction patterns could be refined by including the magnetic reflections corresponding to ferromagnetic structure. The refined magnetic moment of Mn ions is found to be along b axis of the unit cell with a maximum moment of 3.74 μB at 19 K and this value is comparable to the saturation magnetization observed at 20 K from magnetization measurement.