Response of low quartz SiO2 to the presence of an external static electric field: A density functional theory study.
Response of low quartz SiO2 to the presence of an external static electric field: A density functional theory study.
复制标题
低石英 SiO2 对外部静电场存在的响应：密度泛函理论研究。
DOI：
10.1103/physrevb.80.235131
复制
发表时间：
2009
影响因子：
3.7
通讯作者：
M. Rérat
中科院分区：
文献类型：
--
作者：
M. Harb;Pierre Labéguerie;I. Baraille;M. Rérat
本文在密度泛函理论的框架下，系统地研究了$\ensuremath{\alpha}$-quartz ${\text{SiO}}_{2}$对静电场的响应特性。的扭曲的电子密度和晶体结构的应用领域进行了研究，并比较了由Guillot等人获得的x射线散射强度的变化。当一个宏观电场为28.8 kV/cm施加沿着晶体$a$轴。我们的计算表明，实验宏观场主要产生原子位移，电子的贡献可以忽略不计。计算的位移沿着$a$轴与结构因子得到的实验数据吻合较好，而垂直位移较小，两个独立四面体中Si-O键绕$a$轴的转动也较小.在这项工作中，直接间隙，高频介电常数以及弹性和压电张量也计算，以确认我们的计算的准确性。
We present a systematic theoretical study of response properties of $\ensuremath{\alpha}$-quartz ${\text{SiO}}_{2}$ to an external static electric field in the framework of the density functional theory. The distortions of the electron density and crystalline structure by the application of the field are investigated and compared to x-ray scattering intensity variations obtained by Guillot et al. when a macroscopic electric field of 28.8 kV/cm is applied along the crystallographic $a$ axis. Our calculations show that the experimental macroscopic field produces mainly atomic displacements, with a negligible electronic contribution. The calculated displacements along the $a$ axis are in good agreement with the experimental data obtained from structure factors while the perpendicular displacements are found to be smaller, as well as the rotations of the Si-O bonds in the two independent tetrahedra around the $a$ axis. In this work, the direct gap, the high-frequency dielectric constant as well as the elastic and piezoelectric tensors are also computed in order to confirm the accuracy of our calculations.