Characterization of structural transitions and lattice dynamics of hybrid organic–inorganic perovskite CH3NH3PbI3

Characterization of structural transitions and lattice dynamics of hybrid organic–inorganic perovskite CH₃NH₃PbI₃

Jin Feng¹, Ji Jian-Ting², Xie Chao³, Wang Yi-Meng¹, He Shu-Na¹, Zhang Lei⁴, Yang Zhao-Rong⁴, Yan Feng³, Zhang Qing-Ming^{2, 5, †}

(a) Temperature dependence of the lattice constants across the cubic–tetragonal transition. The lattice constants in the tetragonal phase have been converted to their pseudo-cubic parameters using the relationships a * = a tet / 2 and c * = c tet / 2 . (b) Temperature evolution of the (100) diffraction peak. (c) Temperature dependence of parameters c * − a * and the intensity of the (211) peak. The red line is the fitting curve using ( T C − T ) β . (d) Temperature evolution of the (211) diffraction peak in the XRD pattern.