Chemical tuning of dynamic cation off-centering in the cubic phases of hybrid tin and lead halide perovskites.

ABSTRACT: Hybrid halide perovskites combine ease of preparation and relatively abundant constituent elements with fascinating photophysical properties. Descriptions of the chemical and structural drivers of the remarkable properties have often focused on the potential role of the dynamic order/disorder of the molecular A-site cations. We reveal here a key aspect of the inorganic framework that potentially impacts the electronic, thermal, and dielectric properties. The temperature evolution of the X-ray pair distribution functions of hybrid perovskites ABX₃ [A⁺ = CH₃NH₃ (MA) or CH(NH₂)₂ (FA); B²⁺ = Sn or Pb; X^- = Br, or I] in their cubic phases above 300 K reveals temperature-activated displacement (off-centering)

SUBMITTER: Laurita G 

PROVIDER: S-EPMC5621007 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature