Binuclear iron Fe(II) 3-semicarbazone-2,3 dioxoindole complexes as potential organic ferromagnets

The temperature dependence (220-470 K) of the magnetic susceptibility is re ported for the organometallic molecular ferromagnet-chelates of the dinucle ating Fe( II) 3-semicarbazone-2,3 dioxoindole ligand. An average antiferrom agnetic exchange is present in the dinuclear Fe( II) chelates and is charac terised by the coupling constant J= -44.1x10(-4) eV and g=2.08, where the s pin-coupling Hamiltonian is taken as H= -2JS(1)S(2) for Fe(II) centres; the susceptibility studies agree and fit with this result. This study verifies the existence of 3-semicarbazone- 2,3 dioxoindole-bridged di-iron( II) cen tres. The temperature dependence of magnetic moment is illustrated.