Electronic Orders in the Verwey Structure of Magnetite
arXiv:1201.5106 · doi:10.1103/PhysRevB.85.125119
Abstract
Electronic structure calculations of the Verwey ground state of magnetite, Fe3O4, using density functional theory with treatment of on-site Coulomb interactions (DFT+U scheme) are reported. These calculations use the recently-published experimental crystal structure coordinates for magnetite in the monoclinic space group Cc. The computed density distribution for minority spin electron states close to the Fermi level demonstrates that charge order and Fe2+-orbital order are present at the B-type lattice sites to a first-approximation. However, Fe2+/Fe3+ charge differences are diminished through weak bonding interactions of the Fe2+-states to specific pairs of neighboring iron sites that create linear, three-B-atom trimeron units that may be regarded as 'orbital molecules'. Trimerons are ordered evenly along most Fe atom chains in the Verwey structure, but more complex interactions are observed within one chain.
13 pages, 4 figures. Changes for version 2: Fig. 4 and corresponding discussion extended
References in corpus (3)
Cited by in corpus (15)
- Iron Oxide Surfaces
- Structural instability of the rutile compounds and its relevance to the metal-insulator transition of VO2
- Size Dependence of Metal-Insulator Transition in Stoichiometric Fe3O4 Nanocrystals
- Jahn-Teller distortion driven magnetic polarons in magnetite
- Short-Range Correlations in Magnetite above the Verwey Temperature
- Covalency a Pathway for Achieving High Magnetisation in Compounds
- Trimeron-phonon coupling in magnetite
- Oxidation State Dynamics and Emerging Patterns in Magnetite
- Pyroelectric detection of spontaneous polarization in magnetite thin films
- Frenkel pair formation energy for cubic FeO in DFT+U calculations
- Low-Temperature Magnetic Anomaly in Magnetite
- Ultrafast generation of hidden phases via energy-tuned electronic photoexcitation in magnetite
- On the complexity of spinels: Magnetic, electronic, and polar ground states
- Trimeron ordering, bandgap and polaron hopping in magnetite
- The impact of hydrostatic pressure, nonstoichiometry, and doping on trimeron lattice excitations in magnetite during axis switching