Structure of 2p lines in the X-ray photoelectron spectra of low-spin 3d6transition metal compounds

In a survey of Co2p X-ray photoelectron spectra from low-spin Co(III) compounds, it has been found that the 2p 3/2 line shows asymmetric broadening which increases as the ligand field splitting 10 Dq decreases towards its value at the 1 A 1 - 5 T 2 crossover. The effect is attributed to the admixture, induced by the p-d Coulomb interaction of final-state terms associated with electron excitations within the 3d manifold.