Pressure-induced ferroelastic phase transition in Pb3(PO4)2: A neutron-diffraction study

Abstract

A ferroelastic phase change is observed in P${\mathrm{b}}_3$ ${\left(\mathrm{P}{\mathrm{O}}_4\right)}_2$ near 20 kbar at ambient temperature by neutron diffraction. The rhombohedral $\beta$ phase above the transition pressure shows a domain-size broadening similar to that observed in the $\beta$ phase at atmospheric pressure above 180°C.