Magnetic interaction evidence in α-Fe2O3 nanoparticles by magnetization and Mössbauer measurements

VASQUEZ MANSILLA, MARCELO; ZYSLER, ROBERTO D.; ARCIPRETE CARLOS; DIMITRIJEWITS, MARTA I.; SARAGOVI, CELIA; GRENECHE, J. M.

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

Elsevier Science

Año: 1999 vol. 204 p. 29 - 35

0304-8853

Magnetic properties of α-Fe2O3 antiferromagnetic particles of 5 nm mean diameter prepared by sol–gel method were investigated by means of static magnetic measurements and 57Fe Mössbauer spectrometry. The large magnetic moment as well as the anisotropy energy are attributed to the lack of compensation of the antiferromagnetic arrangement essentially located at the surfaces. Zero-field and in-field Mössbauer experiments reveal the existence of magnetic interaction among antiferromagnetic nanoparticles in the sample with higher particle concentration and established the presence of 2 atomic thick surface magnetic layer estimated from a core-shell model.