Oliver J. Weber

TL;DR: In this paper, it was shown that hydrated crystal phases are formed when methylammonium lead iodide perovskite (MAPI) is exposed to water vapor at room temperature and these phase changes are fully reversed when the material is subsequently dried.

TL;DR: The methylammonium cation in [CH3NH3]PbI3 demonstrates increasing positional disorder on heating from 100 K to 352 K and migrates towards the cavity centre with increasing temperature.

TL;DR: In this paper, first-principles lattice dynamics (phonon spectrum) for each phase of the hybrid halide perovskite were reported, and the equilibrium structures compare well to solutions of temperature-dependent powder neutron diffraction.

TL;DR: The structure of black formamidinium lead halide, α-[HC(NH2)2]PbI3, at 298 K has been refined from high resolution neutron powder diffraction data and found to adopt a cubic perovskite unit cell, a = 6.3620(8) A as discussed by the authors.

TL;DR: The calculations indicate that the orientation of [CH3NH3](+) cations has a significant influence on the position of the bandgap suggesting that collective orientation of the organic moieties could result in significant local variations of the optical properties.