Portal de Periódicos da CAPES

Temperature dependence of the nuclear quadrupole interaction at Zr-Ti sites in in the Zr-rich rhombohedral and cubic phases

1998; IOP Publishing; Volume: 10; Issue: 9 Linguagem: Inglês

10.1088/0953-8984/10/9/017

1361-648X

R. E. Alonso, Alberto López García, Alejandro Pedro Ayala, Patricia de la Presa,

Electromagnetic Effects on Materials

In this paper, the hyperfine quadrupole interaction at the Zr-Ti site of (PZT) polycrystalline samples is studied for the first time. Powders for x = 0, 0.1, 0.2, 0.4, 0.6, 0.8, 0.9 and 1 were prepared and characterized by XRD. The lattice constants and space groups were obtained as functions of Ti concentration. PAC analyses were done for ferroelectric PZT for x = 0.9 and 0.8 as a function of temperature, and for x = 0.6 at RT. Also antiferroelectric was analysed. Low-concentration nuclei were used as probes. In the ferroelectric and paraelectric phases of PZT compounds two sites were occupied by probes. For each site the quadrupole frequency, asymmetry and relative distribution width parameters were obtained as functions of temperature above and below the Curie temperature. For only one site was detected with a static quadrupole interaction below and a nuclear spin-relaxation process above it. Furthermore, the temperature dependence of the hyperfine parameters, the possible origin of both quadrupole interactions in PZT and the perturbation that characterizes the cubic phases of and compounds are discussed.