Local structure of ReOFeAs (Re = La, Pr, Nd, Sm) system has been studied as a function of chemical pressure varied due to different rare-earth size. Fe K-edge extended X-ray absorption. ne structure (EXAFS) measurements in the fluorescence mode has permitted to compare systematically the inter-atomic distances and their mean square relative displacements (MSRD). We find that the Fe-As bond length and the corresponding MSRD hardly show any change, suggesting the strongly covalent nature of this bond, while the Fe-Fe and Fe-Re bond lengths decrease with decreasing rare-earth size. The results provide important information on the atomic correlations that could have direct implication on the superconductivity and magnetism of ReOFeAs system, with the chemical pressure being a key ingredient. Copyright (C) EPLA, 2009
Iadecola, A., Agrestini, S., Filippi, M., Simonelli, L., Fratini, M., Joseph, B., et al. (2009). Local structure of ReFeAsO (Re = La, Pr, Nd, Sm) oxypnictides studied by Fe K-edge EXAFS RID A-4797-2009. EUROPHYSICS LETTERS, 87(2) [10.1209/0295-5075/87/26005].
Local structure of ReFeAsO (Re = La, Pr, Nd, Sm) oxypnictides studied by Fe K-edge EXAFS RID A-4797-2009
FRATINI, MICHELA;
2009-01-01
Abstract
Local structure of ReOFeAs (Re = La, Pr, Nd, Sm) system has been studied as a function of chemical pressure varied due to different rare-earth size. Fe K-edge extended X-ray absorption. ne structure (EXAFS) measurements in the fluorescence mode has permitted to compare systematically the inter-atomic distances and their mean square relative displacements (MSRD). We find that the Fe-As bond length and the corresponding MSRD hardly show any change, suggesting the strongly covalent nature of this bond, while the Fe-Fe and Fe-Re bond lengths decrease with decreasing rare-earth size. The results provide important information on the atomic correlations that could have direct implication on the superconductivity and magnetism of ReOFeAs system, with the chemical pressure being a key ingredient. Copyright (C) EPLA, 2009I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
