Thermal expansion and cooling rate dependence of transition temperature in ZrTiO4 single crystal

Thermal expansion in ZrTiO4 single crystal was investigated in the temperature range covering the normal, incommensurate, and commensurate phases. Remarkable change was found at the normal–incommensurate phase transition (TI) in all thermal expansion coefficients a, b, and c. The spontaneous strains χas and χbs along the a and b axes show linear temperature dependence, while the spontaneous strain χcs along the c axis shows a nonlinear temperature dependence. Small discontinuity along the c direction was observed at the incommensurate–commensurate transition temperature, Tc = 845°C. dTI/dP and dTc/dP depend on the cooling rate.