Abstract
Estimates have been made of the volume variation of the total energy of α-Fe as a function of magnetic moment, μ, and electronic configuration. The calculations were done using Wood’s theoretical state densities scaled in such a way that the product of the d-band width and the density of states is held constant. This scaling method is consistent with the results of earlier work by Stern. The overall results indicate that, with increasing pressure, μ➙o slowly in α-Fe and that the electronic structure moves toward d8. The energy line of a paramagnetic phase of Fe is shown to intersect that of α-Fe and become the phase of lowest free energy. This occurs in the region of the α-ε transition and suggest that ε-Fe is paramagnetic. An analysis of the behavior of the d-energies suggests that the lighter transition or pre-transition elements may form stable transition phases under pressure which are also stable at zero pressure.
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References
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Pastine, D.J., Barker, L.M. (1973). A Theory of the α➙ε Transition in Fe and of Possible Higher Pressure Transitions in Fe and in the Lighter Elements of the First Transition Series. In: Rohde, R.W., Butcher, B.M., Holland, J.R., Karnes, C.H. (eds) Metallurgical Effects at High Strain Rates. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-8696-8_11
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