We present X-ray absorption fine structure (EXAFS) data from Y,Pr,Ba and Cu edges for various concentrations of Pr in Y1-xPrxBa2Cu3O7. Analysis of Y K-edge EXAFS shows no evidence for major changes in interatomic distance or in its mean square variation with composition. The individual Ba-O distances have weak compositional dependence. The Pr-O distance is found to vary linearly with composition. We have interpreted the changes in Pr-O distance to conclude the existence of pr in a mixture of Pr3+ and Pr4+ states. The Cu-O coordinates at about 2.4 Angstrom, (the apical oxygen for Cu) appear to have a compositional dependence. Changes in electronic structure are also discussed besides structural changes along with their correlation.
EXAFS and XANES study of structural and electronic changes in Y1-xPrxBa2Cu3O7 / M., Khaled; Saini, Naurang Lal; S. J., Gurman; J. C., Amiss; K. B., Garg. - In: JOURNAL DE PHYSIQUE IV. - ISSN 1155-4339. - STAMPA. - 7:(1997), pp. 1121-1122. (Intervento presentato al convegno 9th International Conference on X-Ray Absorption Fine Structure tenutosi a GRENOBLE, FRANCE nel AUG 26-30, 1996) [10.1051/jp4:19972153].
EXAFS and XANES study of structural and electronic changes in Y1-xPrxBa2Cu3O7
SAINI, Naurang Lal;
1997
Abstract
We present X-ray absorption fine structure (EXAFS) data from Y,Pr,Ba and Cu edges for various concentrations of Pr in Y1-xPrxBa2Cu3O7. Analysis of Y K-edge EXAFS shows no evidence for major changes in interatomic distance or in its mean square variation with composition. The individual Ba-O distances have weak compositional dependence. The Pr-O distance is found to vary linearly with composition. We have interpreted the changes in Pr-O distance to conclude the existence of pr in a mixture of Pr3+ and Pr4+ states. The Cu-O coordinates at about 2.4 Angstrom, (the apical oxygen for Cu) appear to have a compositional dependence. Changes in electronic structure are also discussed besides structural changes along with their correlation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
