Eur. Phys. J. B 44, 209-215 (2005)
https://doi.org/10.1140/epjb/e2005-00116-5

Electronic and magnetic properties of a hexanuclear ferric wheel

Institut für Mathematische Physik, TU Braunschweig, Mendelssohnstraße 3, 38106 Braunschweig, Germany

Corresponding author: ^a h.nieber@tu-bs.de

Received: 17 September 2004
Revised: 14 February 2005
Published online: 20 April 2005

Abstract

The electronic and magnetic properties of the hexanuclear ferric wheel [ LiFe₆(OCH₃)₁₂-(dbm)₆] PF₆ have been studied with all-electron Hartree-Fock and full-potential density functional calculations. The best agreement for the magnetic exchange coupling is at the level of the B3LYP hybrid functional. Surprisingly, the Hartree-Fock approximation gives the wrong sign for the exchange coupling. The local density approximation and the gradient corrected functional PBE strongly overestimate the exchange coupling due to the too large delocalization of the d-orbitals. These findings are supported by results from the Mulliken population analysis for the magnetic moments and the charge on the individual atoms.