Test of the Dynamic-Domain and Critical Scattering Hypotheses in Cubic Methylammonium Lead Triiodide
Nicholas J. Weadock, Peter M. Gehring, Aryeh Gold-Parker, Ian C. Smith, Hemamala I. Karunadasa, Michael F. Toney
We investigate the hypothesis of dynamic tetragonal domains occuring in cubic CH3NH3PbI3 using high-resolution neutron spectroscopy to study a fully deuterated single crystal. The R-point scattering above the 327.5 K tetragonal-cubic phase transition is always resolution-limited in energy and therefore inconsistent with dynamic domain predictions. This behavior is instead consistent with the central peak phenomenon observed in other perovskites. The scattering may originate from small, static, tetragonal-phase domains nucleating about crystal defects, and the temperature dependence demonstrates the transition is first-order
Physical Review Letters
methylammonium lead triiodide, hybrid organic inorganic perovskites, central peak, photovoltaic, critical scattering, structural phase transitions, neutron scattering
, Gehring, P.
, Gold-Parker, A.
, Smith, I.
, Karunadasa, H.
and Toney, M.
Test of the Dynamic-Domain and Critical Scattering Hypotheses in Cubic Methylammonium Lead Triiodide, Physical Review Letters
(Accessed December 10, 2023)