Distinguish the competing inverse-triangular magnetic structures of Mn₃Sn

Distinguish between the competing $Cm'cm'$ and $Cmc'm'$ inverse-triangular magnetic structures of Mn$_3$Sn using measurements or analysis capable of resolving their comparable diffraction fit quality.

Background

Neutron powder diffraction at 300 K was modeled using the Cm′cm′Cm'cm' magnetic space group, while an alternative triangular magnetic order described by Cmc′m′Cmc'm' had recently been proposed. The alternative structure can be generated by rotating the individual spins of the Cm′cm′Cm'cm' structure by 90° within the abab plane.

Because both models provide comparable fits to the available data, the present study cannot determine which in-plane spin arrangement is realized. Resolving this ambiguity would establish the unique magnetic structure of Mn3_3Sn in the inverse-triangular phase, although the authors note that the two arrangements produce similar mPDF patterns and therefore do not affect their local magnetic PDF analysis.

References

The $Cmc'm'$ model yields a comparable fit quality, and therefore the two models cannot be distinguished in the present work.

— Anomalous Hall Response Induced by Correlated Disorder in the Breathing Kagome Lattice Mn$_{3}$Sn  (2609.09699 - Yang et al., 9 Sep 2026) in End Matter, subsection “Magnetic structural determination”