White line in L absorption spectra of rare earths in their oxides and cuprates

A method for curve fitting was used to study and compare the variation in the density of state responsible for the occurrence of the white line associated with the LII and LIII absorption discontinuities of rare earths in their oxides and cuprates. It is observed that the increased covalent character of the rare earth–oxygen bond in rare earth cuprate results in a decrease in the density of the final energy state responsible for the white line.