Structural, vibrational and magnetic properties of monoclinic La2FeMnO6 double perovskite

Abstract

We report the synthesis of the double perovskite La2FeMnO6 and a complete characterization of this system by using X-ray diffraction, Raman and Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), vibrating sample magnetometer, Mossbauer spectroscopy and lattice dynamic calculations. The ambient structure of the La2FeMnO6 was well refined using monoclinic system and P21/n-space group, with two formulas per unit cell (Z = 2). SEM reveals that the sample is formed by particles with quasi-spherical morphology, randomly distributed in clusters. The investigation by Mössbauer spectroscopy identified that the incorporation of iron atoms occurred successfully in the analyzed structure since two paramagnetic phases were identified. The magnetization versus applied field (MxH) curve of La2FeMnO6 at room temperature is discussed. The LFMO double perovskite EPR spectrum indicates the coexistence of paramagnetic resonance (PM) and antiferromagnetic resonance (AFM), being a strong indication of the coexistence of PM and AFM clusters. Moreover, vibrational properties were calculated using a rigid ion model in order to assign the experimental Raman and infrared bands. All these results making the La2FeMnO6 an interesting material with practical applications and for the scientific investigations.