Thermal expansions of Ln2Zr2O7 (Ln = La, Nd, Sm, and Gd) pyrochlore
Thermal expansions of Ln2Zr2O7 (Ln = La, Nd, Sm, and Gd) pyrochlore
复制标题
DOI：
10.1063/1.4722174
复制
发表时间：
2012-05-15
影响因子：
3.2
通讯作者：
Pan, W.
中科院分区：
文献类型：
--
作者：
Feng, J.;Xiao, B.;Pan, W.
用德拜近似和准谐近似结合第一性原理计算研究了稀土锆酸盐(Ln(2)Zr(2)O(7)，Ln=La，Nd，Sm和Gd)焦绿石的热膨胀。得到了C-v和C-p之间的差异。热膨胀的温度依赖性主要是由于声子激发在相对较低的温度下恢复热能所致。当温度远高于德拜温度时，即Ln(2)Zr(2)O(7)化合物在600K以上时，体积系数随温度的升高呈线性增加。计算结果与实验结果吻合较好。(C)2012年美国物理研究所。Pittp：//dx.doi.org/10.1063/1.4722174]
The thermal expansions of the rare earth zirconate (Ln(2)Zr(2)O(7), Ln =La, Nd, Sm, and Gd) pyrochlore were studied by the Debye and quasi harmonic approximation combined with the first principles calculations. The difference between C-v and C-p was obtained. The temperature dependence of thermal expansions is mainly caused by the restoration of thermal energy due to phonon excitations at relatively a low temperature. When the temperature is much higher than Debye temperature, i.e., above 600 K for Ln(2)Zr(2)O(7) compounds, the volumetric coefficient is increased linearly by increasing the temperature. The calculations are in good agreement with the experiments. (C) 2012 American Institute of Physics. Pittp://dx.doi.org/10.1063/1.4722174]