Rare earth L-3-edge x-ray absorption near-edge structure (XANES) spectroscopy has been used to study REOFeAs (RE = La, Pr, Nd, Sm) oxypnictides. The Nd L-3 XANES due to the 2p(3/2) -> 5 epsilon d transition shows a substantial change in both white line (WL) spectral weight and the higher energy multiple scattering resonances with the partial substitution of O by F. A systematic change in the XANES features is seen due to varying lattice parameters with ionic radius of the rare earth. On the other hand, we hardly see any change across the structural phase transition. The results provide timely information on the local atomic correlations showing the importance of the local structural chemistry of the REO spacer layer and interlayer coupling in the competing superconductivity and itinerant striped magnetic phase of the oxypnictides.
RE L-3 x-ray absorption study of REO1-xFxFeAs (RE = La, Pr, Nd, Sm) oxypnictides
Fratini M;
2009
Abstract
Rare earth L-3-edge x-ray absorption near-edge structure (XANES) spectroscopy has been used to study REOFeAs (RE = La, Pr, Nd, Sm) oxypnictides. The Nd L-3 XANES due to the 2p(3/2) -> 5 epsilon d transition shows a substantial change in both white line (WL) spectral weight and the higher energy multiple scattering resonances with the partial substitution of O by F. A systematic change in the XANES features is seen due to varying lattice parameters with ionic radius of the rare earth. On the other hand, we hardly see any change across the structural phase transition. The results provide timely information on the local atomic correlations showing the importance of the local structural chemistry of the REO spacer layer and interlayer coupling in the competing superconductivity and itinerant striped magnetic phase of the oxypnictides.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
