Molecular disorder and translation/rotation coupling in the plastic crystal phase of hybrid perovskites

Jacky Even (1) , Marcello Carignano (2) , Claudine Katan (3)

1 FOTON - Fonctions Optiques pour les Technologies de l'informatiON
2 Qatar Univ
3 ISCR - Institut des Sciences Chimiques de Rennes

The complexity of hybrid organic perovskites calls for an innovative theoretical view that combines usually disconnected concepts in order to achieve a comprehensive picture: i) The intended applications of this class of materials are currently in the realm of conventional semiconductors, which reveal the key desired properties for the design of efficient devices. ii) The reorientational dynamics of the organic component resembles that observed in plastic crystals and therefore requiring a stochastic treatment that can be done in terms of pseudospins and rotator functions. iii) The overall structural similarity with all inorganic perovskites suggests the use of the high temperature pseudo cubic phase as the reference platform on which to build further refinements. In this paper we combine the existing knowledge on these three fields to define a general scenario on which to continue the quest towards a fundamental understanding of hybrid organic perovskites. With the introduction of group theory as the main tool to rationalize the different ideas and the help of molecular dynamics simulations, several experimentally observed properties are naturally explained with possible suggestions for future work.

Domaines: Physique [physics]; Sciences de l'ingénieur [physics]; Chimie

Jacky Even, Marcello Carignano, Claudine Katan. Molecular disorder and translation/rotation coupling in the plastic crystal phase of hybrid perovskites. Nanoscale, 2016, Themed Collection "Perovskites at the nanoscale: from fundamentals to applications", 8 (12), pp.6222-6236. ⟨10.1039/C5NR06386H⟩. ⟨hal-01242390⟩