A variable-temperature Q- and X-band EPR study of spin-crossover iron(III) Schiff base complex
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.
KeywordsIron(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).
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Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest.
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