The magnetic susceptibilities of four iron(III) and five ruthenium(III) compounds, all with the low-spin configuration t52g, have been measured in the range 80–300°K. The data are compared with the theory for a 2T2g 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 t2g electron delocalisation is small in the iron complexes, and in all but one of the ruthenium complexes.