X-RAY ABSORPTION SPECTROSCOPIC STUDIES OF SUBSTITUTED 1-2-3 COMPOUNDS

Abstract

L3-X-ray absorption near edge structure (XANES) of valence susceptible 4f lanthanide ions, Eu and Yb, substituted at the Y-site in 1-2-3 compounds have been recorded with a laboratory XANES setup to find the valence states of Eu and Yb. The K-edges and the associated fine structure of the heavy 3d transition metal dopants, Mn to Ni and Zn, in the 1-2-3 lattice have been measured using synchrotron radiation source at Daresbury laboratory. Edge shifts have been used to (i) determine the valence states of the dopants and (ii) estimate the effective charges on the 3d metal ions. The EXAFS measurements on Fe and Co dopants in 1-2-3 compounds are discussed here in detail. An attempt is made, perhaps for the first time, to present a consolidated account of the K-XANES and EXAFS findings on all the heavy 3d transition metal dopants in the 1-2-3 compounds.