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Updated: May 31, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Mössbauer study of superconducting NdFeAsO(0.88)F(0.12) and its parent compound NdFeAsO
D R Sánchez1, M Alzamora, J Munevar
1Instituto de Física, Universidade Federal Fluminense, Avenida Milton Tavares de Souza, s/n-Campus da Praia Vermelha, 24210-346 Niterói, RJ, Brazil.
Abstract:
(57)Fe Mössbauer spectroscopy has been used to investigate the magnetic order of non-superconducting NdFeAsO (T(N) = 140 K) and superconducting NdFeAsO(0.88)F(0.12) (T(c) = 45 K). A magnetic hyperfine field B(hf) was observed at the (57)Fe nucleus below T(N)∼140 K for NdFeAsO. Below ∼2 K an increase of B(hf) relative to the saturation value was attributed to the transferred B(hf) at the Fe site resulting from the collinear antiferromagnetic (AF) spin structure of the Nd moments. The analysis of the spectra is consistent with a commensurate AF order of Fe spins. No B(hf) is observed in superconducting NdFeAsO(0.88)F(0.12) down to 1.5 K.
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