Multiplet splitting of core-electron binding energies in transition-metal ions

X-ray photoelectron spectra indicate core-electron binding-energy splittings of 6 eV for the 3s levels in MnF2, MnO, and FeF3, and less pronounced effects on the 3s levels in MnO2 and Fe metal. These splittings are considerably reduced from free-ion predictions but agree well with calculations for Mn in a cluster environment. The 3p multiplet splittings are shown to behave in a quantitatively different fashion. © 1969 The American Physical Society.