Mossbauer study of Ba2Ti2Fe2As4O

[摘要] A superconductive Ba2Ti2Fe2As4O oxypnictide sample was synthesized following a solid-state reaction route. X-ray diffraction followed by Rietveld analysis was used for checking the phase content. Fe-57 Mossbauer spectroscopy in transmission geometry was used for characterizing the hyperfine parameters of the iron site. Ba2Ti2Fe2As4O is paramagnetic at least down to 77 K in contrast to the BaFe2As2 parent phase, which exhibits a spin-density order below similar to 140 K. Fitting the isomer shift and spectral absorption data with the Debye model yielded Debye temperatures of 280-320 K. (C) 2020 Elsevier B.V. All rights reserved.

[发布日期] 2020-12-25

[关键词] Pnictide superconductors;Rietveld analysis;Second-order Doppler shift;Fe-57 Mossbauer spectroscopy