Magnetic properties of some iron(III) and ruthenium(III) low-spin complexes

Abstract

The magnetic susceptibilities of four iron(III) and five ruthenium(III) compounds, all with the low-spin configuration t⁵_2g, have been measured in the range 80–300°K. The data are compared with the theory for a ²T_2g ground term in the presence of a low-symmetry ligand-field component, and including electron delocalisation. The splitting of the orbital degeneracy of the term is estimated to be about 500 cm.^–1 in each of the iron compounds, but varies from 0 to 1000 cm.^–1 in the ruthenium compounds. The amount of t_2g electron delocalisation is small in the iron complexes, and in all but one of the ruthenium complexes.