A variable-temperature Q- and X-band EPR study of spin-crossover iron(III) Schiff base complex

  • Milan MazurEmail author
  • Lukaš Pogány
  • Barbora Brachňaková
  • Ivan Šalitroš
Original Paper


The mononuclear iron(III) Schiff base complex was analysed by EPR spectroscopy. The first derivative Q- and X-band EPR spectra of spin-crossover iron(III) complex exhibit the presence of the high spin (S = 5/2) and low spin (S = 1/2) iron(III) state. The variable-temperature EPR measurement confirmed a gradual spin-crossover transition (S = 5/2 ↔ S = 1/2). The possible hysteresis in the thermally induced spin-crossover effect was not detected. The EPR data are in agreement with observed trends in the magnetic measurements reported previously. Note that the EPR studies of this complex have not been performed before. It is obvious that EPR spectroscopy is a powerful method for investigation of the spin-crossover transition and their temperature evolution in the iron(III) complexes.


Iron(III) complex Spin-crossover transition Q- and X-band EPR spectroscopy 



This work was supported by the Slovak Research and Development Agency under the contact No. APVV-15-0053 and by the Scientific Grant Agency of the Slovak Republic (Projects VEGA 1/0026/18 and VEGA 1/0686/17). MM thanks Ministry of Education, Science, Research and Sport of the Slovak Republic for funding within the scheme “Excellent research teams”. This research has been also financially supported by the Ministry of Education, Youth and Sports of the Czech Republic under the project CEITEC 2020 (LQ1601).

Compliance with ethical standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.

Supplementary material

11696_2019_781_MOESM1_ESM.docx (373 kb)
Supplementary material 1 (DOCX 373 kb)


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Copyright information

© Institute of Chemistry, Slovak Academy of Sciences 2019

Authors and Affiliations

  1. 1.Department of Physical Chemistry, Faculty of Chemical and Food TechnologySlovak University of Technology in BratislavaBratislavaSlovakia
  2. 2.Department of Inorganic Chemistry, Faculty of Chemical and Food TechnologySlovak University of Technology in BratislavaBratislavaSlovakia
  3. 3.Central European Institute of TechnologyBrno University of TechnologyBrnoCzech Republic

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