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Direct Evidence of Permanent Octahedra Distortion in MAPbBr3 Hybrid Perovskite
journal contribution
posted on 2017-03-15, 00:00 authored by Andrea Bernasconi, Lorenzo MalavasiIn the present Letter,
we provide direct experimental evidence
of the existence of short-range octahedra distortion in MAPbBr3 in the tetragonal and cubic phases. Such distortion is analogous
to that found in the ordered orthorhombic phase and increases with
temperature and symmetry of the unit cell. Such local distortion is
most probably correlated with the presence of hydrogen bonding between
MA and the PbBr6 framework, and its evolution with temperature
is related to the increase of rotational degrees of freedom of the
MA group.