A monocrystal ofFe 3 O 4 is characterized by resistance, magnetoresistance and magnetic measurements in a temperature range from 4.2 K to 350 K and magnetic field-cycling from −9 T to 9 T. The resistance measurements revealed a metal-insulator Verwey transition (VT) atT v=123.76 K with activation energy E=92.5 meV at T >T v and temperature-substitute for the activation energy below the VT,T 0=E/k B≈3800 K within 70 K–110K. The magnetotransport results independently verified the VT at 123.70 K, with discontinuous change in the magnetic moment ΔM≈0.21 ΔM≈0.21μ B and resistance hysteresis, dependent on the magnetic field in a narrow temperature range of 0.4° around theT v. The magnetic characterization established self consistentlyT v as ≈123.67 K, the jump in the magnetization at the VT≈0.25μ B and confirmed, that the magnetocrystalline anisotropy is the main microscopic mechanism responsible for the magnetization of the monocrystal (88%) with additional natural and imposed defects contributing as 12%.
 R.C. O'Handley:Modern Magnetic Materials, Principles and Applications, John Wiley & Sons Inc., New York, 2000.
 E.J.W. Verwey: “Electronic conduction of magnetite (Fe
4) and its transition point at low temperatures”,Nature (London),Vol. 144, (1939),pp. 327–328; E.J.W. Verwey and P.W. Haayman: “Electronic conductivity and transition point of magnetite (Fe
4)”,Physica, Vol. 8, (1941), pp. 979–987.
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