Skip to Main content Skip to Navigation
Journal articles

Structural Instabilities Related to Highly Anharmonic Phonons in Halide Perovskites

Abstract : Hybrid perovskites have emerged over the past five years as absorber layers for novel high-efficiency low-cost solar cells combining the advantages of organic and inorganic semiconductors. Unfortunately, electrical transport in these materials is still poorly understood. Employing the linear response approach of density functional theory, we reveal strong anharmonic effects and a double-well phonon instability at the center of the Brillouin zone for both cubic and orthorhombic phases of inorganic CsPbI3. Previously reported soft phonon modes are stabilized at the actual lower-symmetry equilibrium structure, which occurs in a very flat energy landscape, highlighting the strong competition between the different phases of CsPbI3. Factoring these low-energy phonons into electron–phonon interactions and band gap calculations could help better understand the electrical transport properties in these materials. Furthermore, the perovskite oscillations through the corresponding energy barrier could explain the underlying ferroelectricity and the dynamical Rashba effect predicted in halide perovskites for photovoltaics.
Document type :
Journal articles
Complete list of metadata

Cited literature [35 references]  Display  Hide  Download
Contributor : Jacky Even <>
Submitted on : Thursday, December 13, 2018 - 3:24:31 PM
Last modification on : Monday, June 14, 2021 - 10:03:18 AM
Long-term archiving on: : Thursday, March 14, 2019 - 2:47:47 PM



Arthur Marronnier, Heejae Lee, Bernard Geffroy, Jacky Even, Yvan Bonnassieux, et al.. Structural Instabilities Related to Highly Anharmonic Phonons in Halide Perovskites. Journal of Physical Chemistry Letters, American Chemical Society, 2017, 8 (12), pp.2659-2665. ⟨10.1021/acs.jpclett.7b00807⟩. ⟨hal-01528877⟩



Record views


Files downloads