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arXiv · 0807.4742

The effect of pressure and spin on the isotopic composition of ferrous iron dissolved in periclase and silicate perovskite

James R. Rustad·Piotr Zarzycki·Maryali P. Sauceda·Qing-zhu Yin
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Abstract

We perform density functional calculations of the equilibrium 57Fe/54Fe ratios for ferrous iron dissolved in periclase and MgSiO3 perovskite at the pressures and temperatures of the Earth's mantle. Pressure increases the partitioning of 57Fe into both phases by a factor of three from the Earth's surface to the core-mantle boundary. In ferropericlase, a large contribution to this increase comes from the electronic transition from high-spin to low-spin iron. Our calculations demonstrate that pressure-induced fractionation can play a major role in determining planetary iron-isotope composition.

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James R. Rustad, Piotr Zarzycki, Maryali P. Sauceda, Qing-zhu Yin. 2008-07-29. The effect of pressure and spin on the isotopic composition of ferrous iron dissolved in periclase and silicate perovskite. https://arxiv.org/abs/0807.4742

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