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arXiv · 1103.6141

Pressure-induced s-band ferromagnetism in alkali metals

Chris J Pickard·R J Needs
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Abstract

First-principles density-functional-theory calculations show that compression of alkali metals stabilizes open structures with localized interstitial electrons which may exhibit a Stoner-type instability towards ferromagnetism. We find ferromagnetic phases of the lithium-IV-type, simple cubic, and simple hexagonal structures in the heavier alkali metals, which may be described as s-band ferromagnets. We predict that the most stable phases of potassium at low temperatures and pressures around 20 GPa are ferromagnets.

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Chris J Pickard, R J Needs. 2011-03-31. Pressure-induced s-band ferromagnetism in alkali metals. https://doi.org/10.1103/physrevlett.107.087201

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