Electron spectroscopy and density-functional study of ‘ferric wheel’ molecules |
| |
Authors: | AV Postnikov SG Chiuzb?ian S Blügel |
| |
Institution: | a Department of Physics, University of Osnabrück, D-49069 Osnabrück, Germany b Institut für Festkörperforschung, Forschungszentrum Jülich, D-52425 Jülich, Germany |
| |
Abstract: | The Li-centered ‘ferric wheel’ molecules with six oxo-bridged iron atoms form molecular crystals. We probed their electronic structure by X-ray photoelectron and soft X-ray emission spectroscopy, having calculated in parallel the electronic structure of a single ‘ferric wheel’ molecule from first-principles by tools of the density-functional theory, using, specifically, the Siesta method. The Fe local moments were found to be 4μB, irrespective of their mutual orientation. Neighbouring atoms, primarily oxygen, exhibit a noticeable magnetic polarization, yielding effective spin S=5/2 per iron atom, that can get inverted as a ‘rigid’ one in magnetic transitions. Corresponding energy preferences can be mapped onto the Heisenberg model with effective exchange parameter J of about −80 K. |
| |
Keywords: | C Ab initio calculations |
本文献已被 ScienceDirect 等数据库收录! |
|