Temperature Dependence of the Hyperfine Interaction at 181Ta in SrHfO3

✍ Scribed by Alberto López-Garcia; Patricia de la Presa; Alejandro Ayala

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 285 KB
• Volume: 159
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2001.9112

✦ Synopsis

The temperature dependence of the quadrupole hyper5ne parameters covering the temperature range from 293 to 1173 K has been measured at 181 Ta probes in SrHfO 3 by perturbed angular correlation spectroscopy. A 6uctuating distribution of quadrupole interactions model has been applied to interpret the data. At low temperatures above &300 K a static, asymmetric, and distributed electric quadrupole interaction was detected. At intermediate temperatures (+600 K) a di4erent quadrupole interaction appears, characterized by a 6uctuating distribution of axially symmetric electric 5eld gradient tensors. Above 873 K, the unique presence of a nuclear spin relaxation machanism shows a second change in the perturbation acting on probes. These changes in the hyper5ne interaction are consistent with the structural phase transitions detected by di4raction techniques. The probe e4ects were also analyzed, comparing 181 Ta with 111 Cd experiments.