Neutron Diffraction Study of the Structure in Cubic CsPbCl3

Abstract

The crystal structure of cubic CsPbCl ₃ was reinvestigated by neutron diffraction technique at 55°C. Two structure models were examined: (i) perovskite structure with anisotropic thermal vibration and (ii) disordered structure having several potential minima for the Cs and Cl atoms, originally proposed by Møller (1959). Both models explain the present neutron data equally well with a reliability index of about 9%. A set of parameters refined on the basis of the structure factor proposed by Møller is, however, revealed to be simply another representation of the perovskite model. As for the perovskite model, anomalously large thermal vibrations were obtained for the Cs and Cl atoms. It is concluded that such anomalous thermal vibrations are characteristics of the phase transitions of this substance.