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Updated: Aug 11, 2026
10:52
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
NMR Evidence for Spontaneous Electronic Chiral Order in URhSn
Y Tokunaga1, T Ishitobi1, H Sakai1
1Japan Atomic Energy Agency, ASRC, Tokai, Ibaraki 319-1195, Japan.
Physical Review Letters
|August 10, 2026
Summary
Nuclear magnetic resonance (NMR) studies reveal symmetry breaking in URhSn
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- URhSn undergoes successive phase transitions at 54 K (T_O) and 16 K (T_C).
- The ferromagnetic nature of the T_C transition is established, but the intermediate phase (T_O to T_C) remains poorly understood.
Purpose of the Study:
- To elucidate the nature of the intermediate phase in URhSn.
- To investigate the symmetry breaking associated with the phase transition at T_O.
Main Methods:
- $^{117}$Sn nuclear magnetic resonance (NMR) measurements.
- Utilized high-quality single crystals of URhSn.
- Analyzed NMR line splittings and their field-direction and site dependences.
Main Results:
- NMR line splittings were observed in the intermediate phase, indicating symmetry breaking.
- The observed splittings are consistent with antiferroquadrupolar ordering.
- The ordering was characterized by the space group P321 (No. 150).
Conclusions:
- The intermediate phase in URhSn is characterized by antiferroquadrupolar ordering.
- This study reveals a novel form of chiral order driven by electronic degrees of freedom.
- The chiral order emerges without an underlying chiral crystal structure in URhSn.
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