Simple correlation between Mn-Ka X-ray emission and Mn 2p X-ray photoelectron spectra for high oxidation number or low-spin manganese compounds

The high-resolution Mn-Kα X-ray emission spectra (XES) and Mn 2p X-ray photoelectron spectra (XPS) for K[MnO₄], K₃[Mn(CN)₅(NO)], K₂[MnO₄] and K₃[Mn(CN)₆] were measured. The first and second compounds which have no unpaired electrons, give symmetrical peaks in Mn-Kα₁ XES and Mn 2p_3/2 XPS spectra. The spectra of the other compounds show asymmetrical lines. When the lines are divided into two Lorenzian (for XES) or Gaussian (for XPS) curves, the energy separation and intensity ratio of the two peaks coincide with each other in both spectroscopies. These results are rationalized by spin-unrestricted DV-Xα molecular-orbital calculations of the anions. The electronic structures of these anions are calculated for their ground state and hole states in 1s and 2p levels. It is concluded that the electronic structures of the compounds in the ground states are conserved in the core hole states. Thus the satellite peaks due to charge transfer are not observed and the peak profiles are governed by the exchange splitting between 2p and valence electrons.