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arXiv · 2211.06904

Static and Dynamic Disorder in Formamidinium Lead Bromide Single Crystals

Guy Reuveni·Yael Diskin-Posner·Christian Gehrmann·Shravan Godse·Giannis G. Gkikas·Isaac Buchine·Sigalit Aharon·Roman Korobko·Constantinos C. Stoumpos·David A. Egger·Omer Yaffe
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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.

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Guy Reuveni, Yael Diskin-Posner, Christian Gehrmann, Shravan Godse, Giannis G. Gkikas, Isaac Buchine, Sigalit Aharon, Roman Korobko, Constantinos C. Stoumpos, David A. Egger, Omer Yaffe. 2022-11-13. Static and Dynamic Disorder in Formamidinium Lead Bromide Single Crystals. https://doi.org/10.1021/acs.jpclett.2c03337

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