Markus Becker
Carl von Ossietzky University Oldenburg, Germany
Title: Tolerance factors for organic-inorganic perovskites: applicability only for high temperature phases
Biography
Biography: Markus Becker
Abstract
In the present work, steric sizes of molecular mono-ammonium cations were calculated by concerning free rotation of the electron density around the center of mass of the molecule. Thereby, structural optimizations were intensively investigated regarding the level of theory and basis sets. A thorough literature study about existing hybrid perovskite compounds revealed a high success rate of predicted stability criteria and 3D phase formation[4]. Furthermore, a case study including the smaller hydroxylammonium (HA+) replacing MA+, confirmed the key role of the cationic size on the structural stability and revealed negligible energy barriers associated with preferred molecular orientations in the cuboctahedron. The newly developed computational approach is well suited for high temperature phases, since it considers thermally enabled movements of the central cation and the associated averaging of inorganic deformations.
