Dielectric and electric studies of the [N(CHub>3 ub>)ub>4 ub>][N(Cub>2 ub>Hub>5 ub>)ub>4 ub>]ZnClub>4 ub> compound at low temperature
- 作者：K. Karoui
- 关键词：[N(CH3)4][N(C2H5)4]ZnCl4 ; ferroelectric ; Equivalent circuit ; Modulus complex ; conductivity
- 刊名：Materials Chemistry and Physics
- 出版年：2012
- 期刊代码：58_02540584
- 类别：ms
- 出版时间：15 March, 2012
- 卷：133
- 期：1
- 页码：1-7
- 文件大小：738 K
摘要
The [N(CHub>3 ub>)ub>4 ub>][N(Cub>2 ub>Hub>5 ub>)ub>4 ub>]ZnClub>4 ub> compound was prepared and characterized by electrical technique. The temperature dependence of the dielectric permittivity shows that this compound is ferroelectric below T = 268 K. The two semi-circles observed in the complex impedance identify the presence of the grain interior and grain boundary contributions to the electrical response in the material. The equivalent circuit is modeled by a combination series of two parallel Rub>P ub>-CPE circuits. The frequency dependent conductivity is interpreted in term of Jonscher's law. The modulus plots can be characterized by the empirical Kohlrausch-Williams-Watts (K.W.W.) function: 蠒(t) = exp [(鈭抰/蟿)up>尾 up>]. The temperature dependence of the alternative current conductivity (蟽ub>p ub>), direct current conductivity (蟽ub>dc ub>) and the relaxation frequency (fub>p ub>) confirm the presence of the ferroelectric-paraelectric phase transition.