On the interpretation of electron-induced X-ray spectra of YBa2Cu3O6+x ceramics

Structure of electron-induced X-ray spectra of YBa2Cu3O6+x ceramics is discussed. It is shown that some spectrum peculiarities change under X-ray and ion irradiation of samples. This enables to separate surface and close to volumetric contributions to the spectrum. Nonempirical calculations of electron charge distribution were used to find differences in binding energies of core shells of ions, located in nonequivalent lattice positions. Correlation of theory and experiment was conducted. It is shown that despite the closeness of calculated effective charges of copper ions the difference of crystal potentials in nonequivalent crystallographic positions enables to explain the structure of Cu2p3/2 spectrum