Valence-skipping and negative-U in the d-band from repulsive local Coulomb interaction
-
Strand, Hugo U. R.
University of Fribourg, Switzerland and University of Gothenburg, Sweden
Published in:
- Physical Review B. - 2014, vol. 90, no. 15, p. 155108
English
We show that repulsive local Coulomb interaction alone can drive valence-skipping charge disproportionation in the degenerate d-band, resulting in effective negative-U. This effect is shown to originate from anisotropic orbital-multipole scattering, and it occurs only for d1,d4,d6, and d9 fillings (and their immediate surroundings). Explicit boundaries for valence-skipping are derived, and the paramagnetic phase diagram for d4 and d6 is calculated. We also establish that the valence-skipping metal is very different, in terms of its local valence distribution, compared to the atomiclike Hund's metal. These findings explain why transition-metal compounds with the aforementioned d-band fillings are more prone to valence-skipping charge order and anomalous superconductivity.
-
Faculty
- Faculté des sciences et de médecine
-
Department
- Département de Physique
-
Language
-
-
Classification
-
Physics
-
License
-
License undefined
-
Identifiers
-
-
Persistent URL
-
https://folia.unifr.ch/unifr/documents/304140
Statistics
Document views: 39
File downloads: