Abstract
We show that formamidinium-based crystals are distinct from methylammonium-based halide perovskite crystals because their inorganic sublattice exhibits intrinsic local static disorder that coexists with a well-defined average crystal structure. Our study combines terahertz-range Raman scattering with single-crystal X-ray diffraction and first-principles calculations to probe the evolution of inorganic sublattice dynamics 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 structural dynamics and phase transitions at higher temperatures.
| Original language | English |
|---|---|
| Pages (from-to) | 1288-1293 |
| Number of pages | 6 |
| Journal | Journal of Physical Chemistry Letters |
| Volume | 14 |
| Issue number | 5 |
| DOIs | |
| State | Published - 9 Feb 2023 |
Bibliographical note
Publisher Copyright:© 2023 The Authors. Published by American Chemical Society.
Funding
The authors thank David Cahen for fruitful discussions and Lior Segev for software development. G.R. acknowledges the support of the Weizmann Institute Sustainability and Energy Research Initiative. O.Y. acknowledges funding from European Research Council (850041 - ANHARMONIC). D.A.E. acknowledges funding from the Alexander von Humboldt Foundation within the framework of the Sofja Kovalevskaja Award, the Technical University of Munich - Institute for Advanced Study (Grant Agreement 291763), and the Deutsche Forschungsgemeinschaft (EXC 2089/1-390776260).
| Funders | Funder number |
|---|---|
| Alexander von Humboldt-Stiftung | |
| Institute for Advanced Study | 291763 |
| European Commission | 850041 - ANHARMONIC |
| Deutsche Forschungsgemeinschaft | EXC 2089/1-390776260 |
| Technische Universität München |