Static and Dynamic Disorder in Formamidinium Lead Bromide Single Crystals

Abstract

We show that formamidinium lead bromide is unique among the halide perovskite crystals because its inorganic sub-lattice exhibits intrinsic local static disorder that co-exists with a well-defined average crystal structure. Our study combines THz-range Raman-scattering with single-crystal X-ray diffraction and first-principles calculations to probe the inorganic sub-lattice dynamics evolution with temperature in the range of 10-300 K. The temperature evolution of the Raman spectra shows that low-temperature, local static disorder strongly affects the crystal's structural dynamics and phase transitions at higher temperatures.

Total 16 pages, 8 figures (including SI). Submitted to The Journal of Physical Chemistry Letters

References in corpus (3)

• Spontaneous Octahedral Tilting in the Cubic Inorganic Caesium Halide Perovskites CsSnX${}_3$ and CsPbX${}_3$ (X = F, Cl, Br, I)
• Dynamic Shortening of Disorder Potentials in Anharmonic Halide Perovskites
• The effects of intrinsic local distortions vs. dynamic thermal motions on the stability and band gaps of cubic oxide and halide perovskites

Cited by in corpus (4)

• Dynamic Nanodomains Dictate Macroscopic Properties in Lead Halide Perovskites
• Using Pressure to Unravel the Structure-Dynamic-Disorder Relationship in Metal Halide Perovskites
• Revealing the Low Temperature Phase of FAPbI${}_3$ using A Machine-Learned Potential
• Kinetically Arrested Twin-Domain State in Formamidinium Lead Iodide