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Electronic structure study by means of X-ray spectroscopy and theoretical calculations of the "ferric star" single molecule magnet

A. F. Takacs·M. Neumann·A. V. Postnikov·K. Kuepper·A. Scheurer·S. Sperner·R. W. Saalfrank·K. C. Prince
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Abstract

The electronic structure of the single molecule magnet system M[Fe(L)2]3*4CHCl3 (M=Fe,Cr; L=CH3N(CH2CH2O)2) has been studied using X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, soft X-ray emission spectroscopy, and density functional calculations. There is good agreement between theoretical calculations and experimental data. The valence band mainly consists of three bands between 2 eV and 30 eV. Both theory and experiments show that the top of the valence band is dominated by the hybridization between Fe 3d and O 2p bands. From the shape of the Fe 2p spectra it is argued that Fe in the molecule is most likely in the 2+ charge state. Its neighboring atoms (O,N) exhibit a magnetic polarisation yielding effective spin S=5/2 per iron atom, giving a high spin state molecule with a total S=5 effective spin for the case of M = Fe.

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A. F. Takacs, M. Neumann, A. V. Postnikov, K. Kuepper, A. Scheurer, S. Sperner, R. W. Saalfrank, K. C. Prince. 2005-11-23. Electronic structure study by means of X-ray spectroscopy and theoretical calculations of the "ferric star" single molecule magnet. https://doi.org/10.1063/1.2155340

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