Neutron diffraction study on nuclear and magnetic structure of (1-x) La0.8Ba0.2MnO3/(x) Bi0.5Na0.5TiO3 composite

Neutron diffraction study on nuclear and magnetic structure of (1-x) La0.8Ba0.2MnO3 / (x) Bi0.5Na0.5TiO3 composite has been carried out. In this research, LBMO (La0.8Ba0.2MnO3) and BNTO (Bi0.5Na0.5TiO3) were each synthesized by the solid state reaction method using high energy milling (HEM). The value of x was varied with 0, 0.4, 0.5, 0.6, and 1.0, namely C1, C2, C3, C4 and C5 sample respectively. Neutron diffraction was conducted using High Resolution Powder Diffractometer (HRPD) to investigate the nuclear and magnetic structure of each sample. Neutron diffraction data was analyzed with Rietveld method using FullProf software. The refinement results show that the crystal structure of C1 was monoclinic while that of C5 was rhombohedral. There were unusual peaks found in C1 which belong to La2O6. With the increase in x composition (C2 to C4), change in lattice parameter was observed but it did not lead to phase transformation. Lattice strain of C1 to C5 were calculated from the FWHM using Scherrer method. The result showed positive strain in samples C1 and C5, meanwhile negative strain was obtained in the rest. It indicates that composite treatment compacts the structure of the material. The magnetic structure of LBMO in C1 to C4 was found to be antiferromagnetic with C2 having the highest magnetic moment of 1.304 µB. This can further be attributed to the application of LBMO and BNTO as electromagnetic wave absorber.