Charge order in magnetite. An LDA+U studyG. K. H. Madsen1, 2 and P. Novák2
1 Department of Chemistry, University of Aarhus - DK-8000 Århus C, Denmark
2 Institute of Physics, Academy of Sciences of the Czech Republic Cukrovarnická 10, 162 53 Praha 6, Czech Republic
received 28 July 2004; accepted in final form 3 January 2005
published online 2 February 2005
The electronic structure of the monoclinic structure of is studied using both the local density approximation (LDA) and the LDA+U. The LDA gives only a small charge disproportionation, thus excluding that the structural distortion should be sufficient to give a charge order. The LDA+U results in a charge disproportion along the c-axis in good agreement with the experiment. We also show how the effective U can be calculated within the augmented plane-wave methods.
71.28.+d - Narrow-band systems; intermediate-valence solids.
71.30.+h - Metal-insulator transitions and other electronic transitions.
71.15.Mb - Density functional theory, local density approximation, gradient and other corrections.
© EDP Sciences 2005