Maghemite


Also found in: Wikipedia.

maghemite

[mag′he‚mīt]
(mineralogy)
γ-Fe2O3 A mineral form of iron oxide that is strongly magnetic and a member of the magnetite series.

Maghemite

 

a mineral, a magnetic modification of the ferric oxide γ — Fe2O3. Generally containing admixtures of FeO and TiO2, maghemite is unstable in the natural state and is readily converted into stable hematite. It crystallizes in the tetragonal (pseudoisometric) system characterized by a defective spinel structure of the magnetite type. Maghemite has a hardness of 5-6 on Mohs’ scale and a density of 4,700-4,900 kg/m3. It is opaque and has a dark brown color with a steel-like hue. Maghemite occurs in nature only in the form of microscopically fine depositions in magnetite oxidation products and in titanomagnetite (with hematite, iron hydroxides). It is sometimes found in limonite and laterite as the product formed during the surface weathering of minerals containing iron.

References in periodicals archive ?
The so-called MNPs usually consist of nanoparticles with a magnetic core composed of magnetite (Fe[sub]3O[sub]4) or maghemite (Fe[sub]2O[sub]3), containing of a type of product termed superparamagnetic iron oxide nanoparticles (SPIONs).
Lo, Removal and recovery of Cr(VI) from wastewater by maghemite nanoparticles, Water Res.
Completely filling anodic aluminum oxide with maghemite nanoparticles by dip coating and
Na, "Synthesis of highly crystalline and monodisperse maghemite nanocrystallites without a size-selection process," Journal of the American Chemical Society, vol.
In this paper, the particle size and morphology of the maghemite and dextran coated maghemite was evaluated by dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM).
Among them, hematite, magnetite and maghemite nanoparticles have particularly promising properties for biomedical applications.
In first category magnetite (Fe3O4) and maghemite (Fe2O3) are included.
Allen, Vibrational spectroscopic characterization of hematite, maghemite and magnetite thin films produced by vapour deposition, ACS appl.
181) These are then aged and oxidized to form small, dispersed maghemite spheres.
magnetite and maghemite, are the most frequently used because of their generally suitable magnetic properties and biological compatibility.
2007): "The Preparation of Magnetite, Goethite, Hematite and Maghemite of Pigment Quality from Mill Scale Iron Waste", Dyes and Pigments, 74, pp.