Author/Authors :
Wang، نويسنده , , J. and Wang، نويسنده , , C.C. and Li، نويسنده , , Q.J. and Yu، نويسنده , , Y. and Zhang، نويسنده , , J. and Zheng، نويسنده , , J. and Cheng، نويسنده , , C. and Li، نويسنده , , Y.D. and Wang، نويسنده , , H. and Huang، نويسنده , , S.G.، نويسنده ,
Abstract :
The dielectric properties of CaF2 single crystals were investigated in the temperature range from room temperature to 773 K and the frequency range of 50 Hz–10 MHz. A Debey-like relaxation and a relaxor-like dielectric anomaly were observed. Raman spectrum and the differential scanning calorimeter measurement revealed the coexistence of native defects of fluorine vacancies ( V F ) and interstitial fluorine ions ( F ′ i ) and external defect of oxygen ions. Impedance analysis showed that the Debey-like relaxation results from the mobility of V F , while the relaxor-like behavior is associated with the relaxation caused by complexes of O ″ − V F .
Keywords :
fluorides , Impedance spectroscopy , Raman spectroscopy , differential scanning calorimetry (DSC) , dielectric properties
