Direct observation of ferroelasticity in Pb3(PO4)2  Pb3(VO4)2

Ferroelasticity has been established in the room temperature phase of Pb3(PxV1-xO4)2, (x ≥ 0.8). The coercitive stress and the spontaneous strain have been determined and found to be 1.6 bars and ca. 3.5 · 10−4 respectively. The effect of domain switching on double refraction and Raman spectra is clearly brought out.