Fig. 3: Time and oxygen partial pressure dependence of the Verwey transition.
From: Slow oxidation of magnetite nanoparticles elucidates the limits of the Verwey transition
a TV as a function of oxidation time. The squares, circles, triangles, and diamonds indicate TV as determined from the magnetization, the XRD measurements, the NMR spectra, and the heat capacity, respectively (details of TV determination are in “Methods”). The dashed line indicates the oxidation time tmin, at which the minimum of TV is observed (in magnetization data). The color-density represents the first derivative of the magnetization, dM/dT, which shows how the Verwey transition is broadened around tmin but then sharpens as the final TV = 95 K value is reached near 2tmin. (b) Time variations of TV from magnetization measurements at different oxygen partial pressures. The inset shows the log–log plot of tmin against P(O2) with a linear fit.
