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Evidence for differentiation in the iron-helicoidal-chain in GdFe$_{3}$(BO$_{3}$)$_{4}$

S. Klimin·D. Fausti·A. Meetsma·L. N. Bezmaternykh·P. H. M. van Loosdrecht·T. T. M. Palstra
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Abstract

We report on a single-crystal X-ray structure study of $GdFe_{3}(BO_{3})_{4}$ at room temperature and at T=90 K. At room temperature $GdFe_{3}(BO_{3})_{4}$ crystallizes in a trigonal space group R32 (No. 155), the same as found for other members of iron-borate family $RFe_{3}(BO_{3})_{4}$. At 90 K the structure of $GdFe_{3}(BO_{3})_{4}$ has transformed to the space group $P3_{1}2_{1}$ (No. 152). The low-temperature structure determination gives new insight into the weakly first-order structural phase transition at 156 K and into the related Raman phonon anomalies. The discovery of two inequivalent iron chains in the low temperature structure provide new point of view on the low-temperature magnetic properties.

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S. Klimin, D. Fausti, A. Meetsma, L. N. Bezmaternykh, P. H. M. van Loosdrecht, T. T. M. Palstra. 2005-05-13. Evidence for differentiation in the iron-helicoidal-chain in GdFe$_{3}$(BO$_{3}$)$_{4}$. https://doi.org/10.1107/s0108768105017362

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