Multiatomic resonant photoemission spectroscopy on CuO and NiO: Observation of antiresonant behavior

The intensity of the O $1s$ core photoemission peak has been measured for CuO and NiO as the photon energy is scanned across the $L_3$ absorption edge of the metal ion. In CuO, the O $1s$ peak shows a typical antiresonant behavior, with a sizable decrease of its cross section at photon energies below the Cu $L_3$ threshold. No detectable effect is observed for NiO. The CuO data are well reproduced by a multiatom resonant photoemission model based on resonant light scattering.