Synthesis, hydrogen-bonded 1D structure, and abrupt spin transition between high-spin (HS) and an ordered [HS-HS-HS-LS] of a mononuclear iron(III) complex [Fe-III(Him)(2)(4-MeOhapen)]CF3SO3 (Him = imidazole, 4-MeOhapen = N,N '-bis-(2-oxy-4-methoxyacetophenylidene)ethylenediamine)

摘要

A SCO iron(III) complex [Fe-III(Him)(2)(4MeOhapen)]CF3SO3 was synthesized, where Him = imidazole and 4-MeOhapen = N,N'-bis(2-oxy-4-methoxyacetophenylidene)ethylenediamine. Fe-III ion has an octahedral coordination geometry with N2O2 donor atoms of the equatorial tetradentate ligand (4-MeOhapen) and two nitrogen atoms of two imidazoles (Him) at the axial positions. The adjacent cations are bridged by CF3SO3 ion through NH center dot center dot center dot O hydrogen bonds between Him and CF3SO3 to give a one-dimensional chain structure {[Fe-III(Him)(2)(4MeO-hapen)]CF3SO3}(1 infinity). The magnetic susceptibility measurements showed that complex exhibits an abrupt spin transition between a single HS phase and a symmetry-breaking [HS-HS-HS-LS] phase and another transition around 80 K. The single-crystal X-ray analyses at 296 and 150 K revealed the structures at a single HS and [HS-HS-HS-LS] states. (C) 2015 Elsevier B.V. All rights reserved.