High‐Resolution In‐Situ Synchrotron X‐Ray Studies of Inorganic Perovskite CsPbBr₃: New Symmetry Assignments and Structural Phase Transitions (Adv. Sci. 18/2021)

Inorganic Perovskites In article number 2003046 by Trevor A. Tyson and co‐workers, single‐crystal diffraction measurements combined with second harmonic generation measurements reveal the absence of inversion symmetry below room temperature in perovskite photovoltaic CsPbBr(3). By combining state‐of‐art experimental methods and modeling, the crystal structure of this perovskite is determined for a broad range of temperatures and pressures. The currently accepted space group assignments are found to be incorrect in a manner which profoundly impacts physical properties. Findings from this study will facilitate the design of solar cells through precise understanding of the structure and properties of CsPbBr(3) and, more generally, the APbX(3) perovskite photovoltaic family. [Image: see text]