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The Bethe-Slater curve revisited; new insights from electronic structure theory.

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 ?-Fe, as in ?-Fe, we find a strong competition in the symmetry-resolved orbital contributions and analyse the differences between the high-spin and low-spin solutions.

SUBMITTER: Cardias R

PROVIDER: S-EPMC5481344 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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The Bethe-Slater curve revisited; new insights from electronic structure theory.

Cardias R R Szilva A A Bergman A A Marco I Di ID Katsnelson M I MI Lichtenstein A I AI Nordström L L Klautau A B AB Eriksson O O Kvashnin Y O YO

Scientific reports 20170622 1

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 ...[more]

PMID: 28642615

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The Bethe-Slater curve revisited; new insights from electronic structure theory.

Publications

The Bethe-Slater curve revisited; new insights from electronic structure theory.

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