Effects of microstructure on the magnetic properties of polycrystalline NiMn2O4 spinel oxides

Author(s)

Freitas Cabral, A. J. ^[1] ; Remedios, C. M. R. ^[2] ; Gratens, X. ^[3] ; Chitta, V. A. ^[3]

Affiliation

^[1] Univ Fed Oeste Para, Santarem, PA - Brazil

^[2] Univ Fed Para, Inst Ciencias Exatas & Nat, Belem, Para - Brazil

^[3] Univ Sao Paulo, Inst Fis, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Journal of Magnetism and Magnetic Materials; v. 469, p. 108-112, JAN 1 2019.
• Web of Science Citations: 1

Abstract

Polycrystalline NiMn2O4 samples were synthesized by sol-gel method at 500 degrees C (S500), 700 degrees C (S700), and 800 degrees C (S800). The three samples were then structurally characterized by X-ray diffraction and Rietveld refinement. Results indicate that samples are single phase and crystallize in the Fd (3) over barm space group with spinel structure. Williamson-Hall analysis shows that samples present different lattice strains. NiMn2O4 compounds show the magnetic transition from ferrimagnetic to paramagnetic at nearly 100 K. Hysteresis loops measured at T = 1.7 K after cooling the samples under magnetic field are asymmetric along the field axis. (AU)

• FAPESP's process: 15/16191-5 - The research in new materials involving high magnetic fields and low temperatures
• Grantee: Gennady Gusev
• Support type: Research Projects - Thematic Grants