Temperature and hydrostatic pressure dependence of vibrational modes in PbTi_1–xZr_xO₃

Abstract

The room temperature Raman spectra of PbTi0.1Zr0.9O3 at hydrostatic pressures up to 68.5 kbar indicate three phase transitions. At 5.71 kbar a new phase appears, most probably the rhombo‐hedral high‐temperature phase, FR(HT) which is in coexistence with the rhombohedral low‐temperature phase FR(HT). Between 8 and 9.1 kbar the relative intensities of all lines change and two additional structures appear. It is likely that this change is due to a transition into the orthorhombic antiferroelectric phase. A further transition between 39.7 and 42 kbar cannot be positively interpreted on the basis of the present data. The temperature dependence of the Raman spectra gives evidence that the additional structure in the FR(LT) phase is due to the doubling of the unit cell, i.e. PbTi1–xZrxO3 seems to show one‐mode behaviour. Copyright © 1977 WILEY‐VCH Verlag GmbH & Co. KGaA