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arXiv · 1812.05255

Lattice vibrations and dynamic disorder in two-dimensional hybrid lead-halide perovskites

Vlad Alexandru Dragomir·Stefanie Neutzner·Claudio Quarti·Daniele Cortecchia·Annamaria Petrozza·Sjoerd Roorda·David Beljonne·Richard Leonelli·Ajay Ram Srimath Kandada·Carlos Silva
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Abstract

By means of non-resonant Raman spectroscopy and density functional theory calculations, we measure and assign the vibrational spectrum of two distinct two-dimensional lead-iodide perovskite derivatives. These two samples are selected in order to probe the effects of the organic cation on lattice dynamics. One templating cation is composed of a phenyl-substituted ammonium derivative, while the other contains a linear alkyl group. We find that modes that directly involve the organic cation are more prevalent in the phenyl-substituted derivative. Comparison of the temperature dependence of the Raman spectra reveals differences in the nature of dynamic disorder, with a strong dependence on the molecular nature of the organic moiety.

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Vlad Alexandru Dragomir, Stefanie Neutzner, Claudio Quarti, Daniele Cortecchia, Annamaria Petrozza, Sjoerd Roorda, David Beljonne, Richard Leonelli, Ajay Ram Srimath Kandada, Carlos Silva. 2018-12-13. Lattice vibrations and dynamic disorder in two-dimensional hybrid lead-halide perovskites. https://arxiv.org/abs/1812.05255

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