Term: Morin transition
https://doi.org/10.1351/goldbook.M04031

Definition:
A transition specific to α-Fe2O3 in which there is a change in the direction of the atomic magnetic moments in the antiferromagnetic state from parallel to perpendicular to the c-axis. Synonymous with spin-flop transition.

Source: PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 587 (https://doi.org/10.1351/pac199466030577)

Citation: 'Morin transition' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M04031

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