Tender X-ray diffraction anomalous fine structure spectroscopy applied to the study of PbSc_0.5Nb_0.5O₃ relaxor ferroelectric oxide

Diffraction anomalous fine structure spectroscopy (DAFS) is a well established technique for characterizing the local structure of elements embedded in complex interfaces and templates when crystallographic and/or site selectivity is needed. DAFS has been effectively applied in the hard X-ray range, where reciprocal space is extended and the absorption edges of the chemical elements are usually well spaced. In this work, we extend the use of DAFS to the tender X-ray range. This energy range is important since it includes the L-edges of second row transition metal elements, which are constituents of functional oxide materials; and some important edges for semiconductors. We present a study of the Nb L-edges in PbSc_0.5Nb_0.5O₃ relaxor ferroelectric oxide, where the use of superstructure reflections provides access to the ordered part of the sample.