X-ray photoelectron spectra of defective nickel oxide

Abstract

Cation-deficient nickel oxides have been investigated by X-ray photoelectron spectroscopy. The high-binding-energy features in the O(1s), Ni(2p) X.p.s. of defective NiO are described as multielectron final states, induced by defective sites. These sites are described as (NiO₆)^9– molecular clusters because of the d hole. The energy shift between the main peak and the satellite, in both the O(1s) and Ni(2p) X.p.s. spectra, is due to a change in the ionic charge and in the oxygen coordination induced by cation vacancies.