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

TL;DR

This study combines X-ray spectroscopy and density functional calculations to analyze the electronic structure of a single molecule magnet, revealing details about its valence band, charge state, and magnetic properties.

Contribution

It provides a comprehensive analysis of the electronic structure of the ferric star single molecule magnet using combined experimental and theoretical methods, with good agreement between data and calculations.

Findings

Valence band mainly between 2 eV and 30 eV

Fe likely in 2+ charge state

High spin state with effective spin S=5

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.