Abstract
New stable Fe(III) complexes of tetraamide [N-6], [N-8] and [N-10] macrocyclic ligands are reported. One of them, [N-10] is dinucleating, with two Fe(III) nuclei in the macrocyclic cavities. The structural features have been discussed on the basis of analytical, ESI mass, FT-IR, electronic, H-1 and C-13 NMR spectral studies. Magnetic moment studies indicate presence of anti-ferromagnetically coupled (Fe3+-Fe3+ = S-5/2-S-5/2) spin-spin interactions in the dinuclear [N-10] complex. Fe Mossbauer measurements confirm Fe(+/- 3/2 -> +/- 1/2) nuclear transitions supporting high-spin configuration of Fe(III) nuclei with the presence of Kramer's double degeneracy. (c) 2008 Published by Elsevier B.V.