Imperial College London
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Dr Jarvist Moore Frost

Faculty of Natural Sciences, Department of Chemistry

Royal Society URF (Lecturer)
 
 
 
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Contact

 

jarvist.frost Website

 
 
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Location

 

601FMolecular Sciences Research HubWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@article{Xi:2017:10.1021/acs.jpclett.7b02423,
author = {Xi, R and Skelton, JM and da, Silva EL and Frost, JM and Walsh, A},
doi = {10.1021/acs.jpclett.7b02423},
journal = {JOURNAL OF PHYSICAL CHEMISTRY LETTERS},
pages = {4720--4726},
title = {Spontaneous Octahedral Tilting in the Cubic Inorganic Cesium Halide Perovskites CsSnX3 and CsPbX3 (X = F, CI, Br, I)},
url = {http://dx.doi.org/10.1021/acs.jpclett.7b02423},
volume = {8},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The local crystal structures of many perovskite-structured materials deviate from the average space-group symmetry. We demonstrate, from lattice-dynamics calculations based on quantum chemical force constants, that all of the cesium–lead and cesium–tin halide perovskites exhibit vibrational instabilities associated with octahedral titling in their high-temperature cubic phase. Anharmonic double-well potentials are found for zone-boundary phonon modes in all compounds with barriers ranging from 108 to 512 meV. The well depth is correlated with the tolerance factor and the chemistry of the composition, but is not proportional to the imaginary harmonic phonon frequency. We provide quantitative insights into the thermodynamic driving forces and distinguish between dynamic and static disorder based on the potential-energy landscape. A positive band gap deformation (spectral blue shift) accompanies the structural distortion, with implications for understanding the performance of these materials in applications areas including solar cells and light-emitting diodes.
AU  - Xi,R
AU  - Skelton,JM
AU  - da,Silva EL
AU  - Frost,JM
AU  - Walsh,A
DO  - 10.1021/acs.jpclett.7b02423
EP  - 4726
PY  - 2017///
SN  - 1948-7185
SP  - 4720
TI  - Spontaneous Octahedral Tilting in the Cubic Inorganic Cesium Halide Perovskites CsSnX3 and CsPbX3 (X = F, CI, Br, I)
T2  - JOURNAL OF PHYSICAL CHEMISTRY LETTERS
UR  - http://dx.doi.org/10.1021/acs.jpclett.7b02423
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000412720100013&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - http://hdl.handle.net/10044/1/54176
VL  - 8
ER  -
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