Low Temperature Crystal Structure and 57Fe Moessbauer Spectroscopy of Sr3Sc2O5Fe2As2

TL;DR

This study investigates the low-temperature crystal structure and iron local environment of Sr3Sc2O5Fe2As2 using X-ray diffraction and Moessbauer spectroscopy, revealing structural stability and no magnetic ordering down to 10 K.

Contribution

It provides detailed structural and spectroscopic data on Sr3Sc2O5Fe2As2 across a range of temperatures, highlighting its stability and electronic properties.

Findings

Anisotropic lattice contraction with decreasing temperature.

No structural instability or magnetic ordering detected.

Increase in isomer shift indicating changes in electronic environment.

Abstract

The crystal structure of the layered iron arsenide Sr3Sc2O5Fe2As2 was determined between 300 and 10 K. The lattice parameters of the tetragonal cell decrease anisotropically according to delta(c)/c : delta(a)/a = 4.2, which results in a slight flattening of the As-Fe-As bond angle within the FeAs layers. No indication of a structural instability could be detected. 57Fe Moessbauer spectroscopic data show a single signal at 4.2, 77, and 298 K, respectively, subjected to quadrupole splitting. The isomer shift increases from 0.36(1) mm/s at 298 K to 0.49(1) mm/s at 4.2 K. No indication for magnetic ordering was found.