High-Spin Mononuclear Iron(III) Complexes with Pentadentate Schiff Base Ligands: Structural Analysis and Magnetic Properties

Lukáš Pogány; Ján Moncol; Ján Pavlik; Milan Mazúr; Ivan Šalitroš

doi:10.1002/cplu.201800658

High-Spin Mononuclear Iron(III) Complexes with Pentadentate Schiff Base Ligands: Structural Analysis and Magnetic Properties

Chempluschem. 2019 Apr;84(4):358-367. doi: 10.1002/cplu.201800658.

Authors

Lukáš Pogány¹, Ján Moncol¹, Ján Pavlik¹, Milan Mazúr², Ivan Šalitroš^{1

3}

Affiliations

¹ Department of Inorganic Chemistry Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava, 81237, Slovakia.
² Department of Physical Chemistry Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Bratislava, 81237, Slovakia.
³ Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00 Brno, Czech Republic.

PMID: 31939215
DOI: 10.1002/cplu.201800658

Abstract

Various substituted 2-hydroxybenzophenones were combined with aliphatic linear triamines to form pentadentate Schiff base ligands. Twelve new iron(III) complexes with the general formula [Fe(L_n )X].mCH₃ CN (n=1-10; X=N₃^- , NCS^- or NCSe^- ; m=0-2) have been synthesized, and spectrally as well as structurally characterized. The structural analysis revealed a notable dependence of coordination polyhedra deformation as well as the spatial configuration of donor atoms on the length and symmetry of the Schiff base ligands. The magnetic properties of the compounds were investigated and the permanent high-spin state (S=5/2) for all reported compounds was established, and allowed calculation of zero-field-splitting parameters as well as coupling constants, which were further confirmed with DFT calculations. The solid-state EPR spectra were recorded at 293 K and 98 K, and in accordance with the magnetic measurements, showed a high-spin state in the measured temperature range.

Keywords: N,O-ligands; Schiff bases; density functional calculations; iron(III) complexes; magnetic properties.

Publication types

Research Support, Non-U.S. Gov't