Record Details

Title:
The Bethe-Slater curve revisited; new insights from electronic structure theory
Affiliation(s):
EuXFEL staff, Other
Author group:
Theory
Topic:
Scientific area:
Abstract:
The Bethe-Slater (BS) curve describes the relation between the exchange coupling and interatomic distance. Based on a simple argument of orbital overlaps, it successfully predicts the transition from antiferromagnetism to ferromagnetism, when traversing the $3d$ series. In a previous article [Phys. Rev. Lett. 116, 217202 (2016)] we reported that the dominant nearestneighbour (NN) interaction for 3d metals in the bcc structure indeed follows the BS curve, but the trends through the series showed a richer underlying physics than was initially assumed. The orbital decomposition of the inter-site exchange couplings revealed that various orbitals contribute to the exchange interactions in a highly non-trivial and sometimes competitive way. In this communication we perform a deeper analysis by comparing $3d$ metals in the bcc and fcc structures. We find that there is no coupling between the $E _{g}$ orbitals of one atom and $T _{2g}$ orbitals of its NNs, for both cubic phases. We demonstrate that these couplings are forbidden by symmetry and formulate a general rule allowing to predict when a similar situation is going to happen. In γ-Fe, as in α-Fe, we find a strong competition in the symmetry-resolved orbital contributions and analyse the differences between the high-spin and low-spin solutions.
Imprint:
Nature, 2017
Journal Information:
Scientific Reports, 7 (1), 4058 (2017)
Related external records:
Language(s):
English
Record appears in:

Export