structural transition

https://doi.org/10.1351/goldbook.S06062
A reversible or irreversible transition that involves a change of the crystal structure. Example: The transition of NH4Cl at 469 K from a CsCl-type structure to a NaCl-type structure.
Source:
PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 591 (https://doi.org/10.1351/pac199466030577)