X-ray emission and photoelectron spectra, and the location of fluorine atoms in strontium and calcium copper oxyfluorides

Abstract

X-ray emission and photoelectron spectra of Sr2CuO2F2+delta, Sr1.4Ba0.6CuO2F2+delta. CaSrCuO2F2+delta, and Ca2CuO2F2+delta cuprates are presented. It is found that the XPS F 1s binding energies of Sr2CuO2F2+delta and Ca2CuO2F2+delta are different (Delta E similar to 1.3 eV) and those of Sr1.4Ba0.6CuO2F2+delta and CaSrCuO2F2+delta have intermediate values. These differences in x-ray photoelectron spectra are attributed to the different preferential location of fluorine atoms in structures related to La2CuO4 and Nd2CuO4. The results obtained are in accordance with measurements of F K alpha x-ray emission spectra of the same compounds.