Isolation of a singly oxo-bridged Fe(III) dinuclear complex: Synthesis, crystal structure, spectroscopic and magnetic studies

摘要

The mu-oxo dinuclear complex {Fe2O(tptz)(2)[N(CN)(2)](2)(NO3)(2)} (1) (where tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine) has been synthesised and characterised by elemental analysis, FT-IR, UV-vis, cyclic voltammetry, Mossbauer spectroscopy, and variable-temperature magnetic susceptibility measurements and single crystal X-ray diffraction. The iron centres have a pentagonal-bipyramidal geometry. The dimeric neutral complex exhibits typical Fe-mu-O bond lengths of 1.763(1) angstrom and a bridge angle of 180.00 degrees. The Fe center dot center dot center dot Fe separation is 3.526(3) angstrom. The Mossbauer spectrum at room temperature consists of one quadrupole doublet with an isomer shift of 0.41 mm/s and a quadrupole splitting of 1.12 mm/s. Variable-temperature magnetic susceptibility measurements have been measured in the temperature range 300-2 K, revealing an intramolecular antiferromagnetic coupling (J = -211.6 cm(-1)). (C) 2006 Elsevier B.V. All rights reserved.