High-Pressure Structural and Optical Studies of Pure Low-Dimensional Cesium Lead Chlorides CsPbCl and CsPbCl.

We report high-pressure single-crystal X-ray diffraction, optical absorption, and photoluminescence investigations of all-inorganic perovskite-related materials CsPbCl and CsPbCl. The crystal structure of CsPbCl, composed of alternate layers of Cs cations and Pb-Cl frameworks, is stable under pressure up to at least 4.2 GPa.