16 декабря, 2015 
Pokraskin Chromium dioxide [12018-01-8], chromium(IV)oxide, CrO2, is a ferromagnetic material with a specific saturation magnetization Ms/p of 132 A m2 kg-1 at 0 K, corresponding to the spin of two unpaired electrons per Cr4+ ion. The Ms/p value of CrO2 at room temperature is ca. 100 A m2 kg-1 [5.17]; CrO2 magnetic pigments reach values of 77-92 A m2 kg-1. The material crystallizes with a tetragonal rutile lattice in the form of small needles, which have the desired magnetic shape anisotropy. The morphology of the particles can be varied with several dopants, particularly antimony and tellurium [5.18]. The coercive field strength can be controlled between ca. 30 and 75 kA m-1 (in addition to shape) by doping with transition metal ions, which modify the magneto-crystalline anisotropy of the material; the Fe3+ ion being industrially important [5.19].
5.1.3.2
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