Title :
Loosely associated ion interaction in the oxide and oxyfluoride pyrochlores
Author :
Cai, Xiukai ; Zhang, Liangying ; Yao, Xi
Author_Institution :
Electron. Mater. Res. Lab., Xi´´an Jiaotong Univ., China
Abstract :
A dielectric relaxation phenomenon was observed in the substituted pyrochlores. The dielectric behavior could be treated according to the Debye model. The activation energy derived from a coincidental determination of the temperature and frequency dependence of loss factors is approximately 0.23 eV, which can be related to a jump of a loosely associated ion pair formed by the replacement of a cation with different valence and the corresponding formation of a vacancy at normally occupied ion site. The period of atom vibration is of the order of 10-12 sec or so. The influence of chemical compositions is discussed
Keywords :
dielectric losses; dielectric relaxation; ferroelectric materials; permittivity; vibrational modes; 0.23 eV; 1E-12 s; Debye model; activation energy; atom vibration period; chemical compositions; dielectric behavior; dielectric relaxation phenomenon; frequency dependence; loosely associated ion interaction; normally occupied ion site; oxide pyrochlores; oxyfluoride pyrochlores; substituted pyrochlores; temperature dependence; vacancy; Ceramics; Conducting materials; Dielectric constant; Dielectric loss measurement; Dielectric losses; Dielectric materials; Energy loss; Frequency; Temperature dependence; Vibration measurement;
Conference_Titel :
Applications of Ferroelectrics, 1994.ISAF '94., Proceedings of the Ninth IEEE International Symposium on
Conference_Location :
University Park, PA
Print_ISBN :
0-7803-1847-1
DOI :
10.1109/ISAF.1994.522441
