In order to understand the mechanism of the structural phase transition in CH 3 NH 3 PbBr 3 , neutron diffraction data from the single crystal is analyzed by the least-squares method and the maximum entropy method. The disordered configuration of a methylammonium ion in a cage surrounded by eight PbBr 6 octahedrons is identified unambiguously. With comparing the low-temperature structure, the transition is characterized by the condensation of the rotational motion of the PbBr 6 octahedron around the Pb-Br axis, which accompanies the partial ordering of the methylammonium ion to reduce the site symmetry.
No takes yet. Share an insight, caveat, or question.
Mashiyama et al. (2007) studied this question.
Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context: