Abstract
X-ray absorption spectroscopy has been used to study superconducting compounds with the composition (Ba,Sr for x=0 to 0.3 X-ray absorption measurements at the Cu K edge indicate that the copper valence is 2+ for all dopant concentrations, and that the mean square relative displacements for Cu-O nearest neighbors are approximately the same for all compositions, with an average characteristic temperature of 570±30 K. Measurements at the La edge suggest that the number of empty states near the Fermi energy with O 2p character increases with dopant concentration.
- Received 18 February 1987
DOI:https://doi.org/10.1103/PhysRevB.35.7187
©1987 American Physical Society