Anisotropic atomic displacements, local orthorhombicity and anomalous local magnetic moment in BaKFeAs superconductor.

We have investigated the in-plane local structure of the BaKFeAs superconductor by polarized Fe K-edge extended X-ray absorption fine structure (EXAFS) measurements with temperature. The near neighbor bond distances and their stiffness, measured by polarized EXAFS in two orthogonal directions, are different suggesting in-plane anisotropy of the atomic displacements and local orthorhombicity in the title system. The X-ray absorption near edge structure (XANES) spectra reveal anisotropy of valence electronic structure that changes anomalously below ∼100 K.

Anisotropic Local Structure of SrFeNiAs (x = 0.00, 0.16, and 0.23) Superconductor Probed by Polarized X-ray Absorption Fine Structure Measurements.

We have investigated the effect of the Ni substitution on the local structure and the valence electronic states of the SrFe2-xNixAs2 (x = 0.00, 0.16, and 0.

Mn substitution effect on the local structure of La(FeMn)AsO studied by temperature dependent x-ray absorption measurements.

The local structure of La(FeMn)AsO has been investigated using temperature dependent Fe K-edge extended x-ray absorption fine structure (EXAFS) measurements. The EXAFS data reveal distinct behavior of Fe-As and Fe-Fe atomic displacements with a clear boundary between⩽ 0.02 and> 0.

Temperature dependent local atomic displacements in NaSnAs system.

NaSnAs is mechanically exfoliable layered van der Waals (vdW) Zintl phase that is getting interesting due to its low thermal conductivity and recently observed superconductivity. Here, we have investigated the temperature dependent local structure of NaSnAs by a combined analysis of As K-edge and Sn K-edge extended x-ray absorption fine structure measurements. The system is intrinsically disordered with the interatomic distances largely consistent to those estimated by average structure measurements.

The electronic structure of AgSnSe (x = 0.0, 0.1, 0.2, 0.25 and 1.0).

We have studied the valence electronic structure of AgSnSe (x = 0.0, 0.1, 0.