Valence States of Metal Ions in $La_{0.7}Ce_{0.3}MnO_3$ Thin Films

We report valence states of ions in $La_{0.7}Ce_{0.3}MnO_3$ thin films grown by a reactive dc magnetron sputtering. The measurements were performed by means of high-energy X-ray photoelectron spectroscopy using synchrotron radiation. It was found that Ce ion in the compound is either in tetravalent or trivalent chemical state, manganese is in divalent, trivalent and tetravalent states, while La ion existing in oxide and hydroxide chemical species is in trivalent state