DOPING DEPENDENCE OF NI 2P X-RAY-ABSORPTION SPECTRA OF M(X)NI(1-X)O (M=LI,NA)

In this paper we give a description of the doping dependence of the Ni 2p x-ray-absorption spectra of M(x)Ni(1-x)O (M=Li,Na). We will show t hat a description beyond an atomic-multiplet calculation is required. To study intermediate doping levels use will be made of a two-metal-si te cluster, where one side functions as a hole reservoir. From this st udy it follows that holes are most likely on the oxygen atoms of the N iO6 units around the Li impurities.