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Non-collinear magnetism in iron at high pressures

R. E. Cohen
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Abstract

Using a first principles based, magnetic tight-binding total energy model, the magnetization energy and moments are computed for various ordered spin configurations in the high pressure polymorphs of iron (fcc, or $γ$-Fe, and hcp, or $ε$-Fe), as well ferromagnetic bcc iron ($α$-Fe). For hcp, a non-collinear, antiferromagnetic, spin configuration that minimizes unfavorable ferromagnetic nearest neighbor ordering is the lowest energy state and is more stable than non-magnetic $ε$ iron up to about 75 GPa. Accounting for non-collinear magnetism yields better agreement with the experimental equation of state, in contrast to the non-magnetic equation of state, which is in poor agreement with experiment below 50 GPa.

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R. E. Cohen. 2003-01-31. Non-collinear magnetism in iron at high pressures. https://doi.org/10.1016/j.pepi.2004.02.002

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