Synthesis, structure, and magnetic properties of the trans-difluoro-bis-phenoxo-bridged iron(III) complex FeIII2(BBPA)2F2 (H2BBPA = N,N-bis(2-hydroxybenzyl)-N-(2-pyridylmethyl)amine)

Abstract

The bis-phenoxo-bridged dinuclear iron(III) compound Fe2(BBPA)2F2 (H2BBPA = N,N-bis(2-hydroxybenzyl)-N-(2-pyridylmethyl)amine) was structurally and magnetically characterized. It has distorted octahedral iron(III) centers with each iron(III) site having two cis-Fe(BBPA)F fragments that are bridged by two μ-phenoxo oxygen atoms. The dinuclear compound has a singlet ground state and thermally populated S = 5 undecet excited state 114 cm−1 above the ground state as the magnetic susceptibility can be fit to the Van Vleck dimer equation (H = −2JSa·Sb) with g = 2.02, J/kB = −15 K (−10.4 cm−1), and a room temperature effective moment of 7.16 μB/FeIII2 in accord with weak antiferromagnetic coupling within the iron(III) dimer.