Ferroelastic domains in lead phosphate αPb3(PO4)2

Abstract
Lead Phosphate Pb3(P04)2 undergoes a transition at T c = 180.5°C from a low-temperature monoclinic phase (phase α belonging to the monoclinic space group C2h 6) to a high-temperature rhombohedral phase (phase β, D5d 3).1,2 The monoclinic phase is ferroelastic and three kinds of ferroelastic domains (or twins) have been previously observed by Brixner.2