Orbital splittings for some high-spin tetragonal complexes of iron(II) from Mössbauer and electronic spectra

Abstract

Mössbauer quadrupole splittings are reported for the compounds FeL₄X₂(L = isoquinoline or γ-picoline, X = Cl, Br, l, or NCS) and Fepy₄X₂(X = Cl or NCS) and the splittings of the t_2g orbitals are deduced therefrom. It is concluded that for the halogeno-complexes d_xy lies lowest, but that this may not be so for the isothiocyanato-compounds. The results are correlated with the electronic spectra and magnetic moments of the iron(II) compounds, and with the orbital splittings previously found for the corresponding nickel(II) complexes.