论文标题
卤化物钙钛矿中的动态倾斜
Dynamical tilting in halide perovskites
论文作者
论文摘要
由于其特定的物理特性，例如超导性，铁电性和光活性，自然和合成的钙壶是广泛使用的功能材料。这些特性中的许多与八面体单元的静态或动态运动有关。然而，目前缺少钙钛矿晶体结构，化学键和物理特性之间的关系。几项研究表明，八面体单位的非谐运动产生的动态障碍的存在，例如在卤化物钙钛矿结构中。在这项工作中，我们为简单的perovskites $ \ rm abx_3 $得出所有可能的空间群，并带有动态八面体倾斜。派生的空间组扩展了已建立的空间组表作为静态倾斜的空间组表，该表由[Glazer，A。Acta Cryst。 B 1972，28，3384-3392; Aleksandrov，K。Ferroelectrics1976，24，801-805;霍华德（C.J.），斯托克斯（Stokes） Acta Cryst。 B 1998，54，782-789]。我们通过分析最近科学出版物中报道的钙钛矿的结构数据来证明动态倾斜度的普遍性，并讨论相应结构中动态倾斜的特征。最后，我们讨论动态障碍对卤化物钙钛矿物理特性的可能影响。
Naturals and synthetic perovskites are widely used functional materials thanks to their particular physical properties, such as superconductivity, ferroelectricity and photo-activity. Many of these properties are related to static or dynamic motion of octahedral units; Yet a full understanding of the relationships between perovskite crystal structure, chemical bonding and physical properties is currently missing. Several studies indicate the existence of dynamic disorder generated by anharmonic motion of octahedral units e.g. in halide perovskite structures. In this work, we derive all possible space groups for simple perovskites $\rm ABX_3$ with dynamical octahedral tilting. The derived space groups extend the well established space group tables for static tiltings by [Glazer, A. Acta Cryst. B 1972, 28, 3384-3392; Aleksandrov, K. Ferroelectrics 1976, 24, 801-805; Howard, C.J., Stokes, H.T. Acta Cryst. B 1998, 54, 782-789]. We demonstrate ubiquity of dynamical tilting by analysing the structural data for perovskites reported in recent scientific publications and discuss the signature of dynamic tilting in the corresponding structures. Finally, we discuss the possible influence of dynamic disorder on the physical properties of halide perovskites.
