Crystallite size dependence on the magnetic properties of nanocrystalline magnetite powders

doi:10.1016/S0304-8853(97)01004-4

Journal of Magnetism and Magnetic Materials

Volume 176, Issues 2–3, 2 December 1997, Pages L89-L92

https://doi.org/10.1016/S0304-8853(97)01004-4 Get rights and content

Abstract

Single phase magnetite powders with crystallite sizes ranging from 8–50 nm were synthesised and studied using X-ray diffraction and Mössbauer spectroscopy. Lattice parameters were seen to decrease at very small crystallite sizes. Quadrupole splitting of the B sites increased with decreasing crystallite size before the spectrum collapsed into a doublet at the smallest sizes. These observations have been explained in terms of high surface-to-volume ratios in the small nanocrystals creating excessive lattice strain and large electric field gradients.

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Letter to the editorCrystallite size dependence on the magnetic properties of nanocrystalline magnetite powders

Abstract

Appl. Surf. Sci.

Nanostructured Mater.

Ann. Phys.

J. Phys. Soc. Japan

J. Appl. Crystallogr.

Letter to the editor
Crystallite size dependence on the magnetic properties of nanocrystalline magnetite powders