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arXiv · 0704.2267

Infrared Optical Properties of Ferropericlase (Mg1-xFexO): Experiment and Theory

Tao Sun·Philip B. Allen·David G. Stahnke·Steven D. Jacobsen·Christopher C. Homes
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Abstract

The temperature dependence of the reflectance spectra of magnesium oxide (MgO) and ferropericlase (Mg1-xFexO, for x=0.06 and x=0.27) have been measured over a wide frequency range (~50 to 32000 cm-1) at 295 and 6 K. The complex dielectric function has been determined from a Kramers-Kronig analysis of the reflectance. The spectra of the doped materials resembles pure MgO in the infrared region, but with much broader resonances. We use a shell model to calculate the dielectric function of ferropericlase, including both anharmonic phonon-phonon interactions and disorder scattering. These data are relevant to understanding the heat conductivity of ferropericlase in the earth's lower mantle.

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Tao Sun, Philip B. Allen, David G. Stahnke, Steven D. Jacobsen, Christopher C. Homes. 2007-04-18. Infrared Optical Properties of Ferropericlase (Mg1-xFexO): Experiment and Theory. https://doi.org/10.1103/physrevb.77.134303

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