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Magnetovolume instabilities in the pressure dependence of the K-edge circular dichroism of Fe3C Invar particles

E. Duman·M. Acet·E. F. Wassermann·J. P. Itie·F. Baudelet·O. Mathon·S. Pascarelli
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Abstract

The p-electrons of carbon in the interstitial compound Fe3C hybridize with the Fe d-band and enhance the valence electron concentration of Fe from 8 to 8.67. At this concentration, substitutional 3d transition metals and alloys exhibit strong moment-volume coupling phenomena and associated magnetovolume instabilities, otherwise known as the Invar effect. For this reason, Fe3C is also expected to incorporate a strong magnetovolume instability, and therefore, we examine the pressure dependence of the of the K edge x-ray magnetic circular dichroism in Fe3C at ambient temperature and pressures up to 20 GPa. We and clear evidence for a high-moment to low-moment transition at about 10 GPa.

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E. Duman, M. Acet, E. F. Wassermann, J. P. Itie, F. Baudelet, O. Mathon, S. Pascarelli. 2004-10-06. Magnetovolume instabilities in the pressure dependence of the K-edge circular dichroism of Fe3C Invar particles. https://arxiv.org/abs/cond-mat/0410156

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