The Library
Tolerance factor control of uniaxial negative thermal expansion in a layered perovskite
Tools
Tools
Tools
Ablitt, Chris, McCay, Harriet, Craddock, Sarah, Cooper, Lauren, Reynolds, Emily, Mostofi, Arash A., Bristowe, Nicholas C., Murray, Claire A. and Senn, Mark S. (2020) Tolerance factor control of uniaxial negative thermal expansion in a layered perovskite. Chemistry of Materials, 32 (1). pp. 605-610. doi:10.1021/acs.chemmater.9b04512 ISSN 0897-4756.
![[img]](https://wrap.warwick.ac.uk/style/images/fileicons/application_pdf.png) |
PDF
WRAP-Tolerance-factor-control-uniaxial-negative-Senn-2020.pdf - Accepted Version Embargoed item. Restricted access to Repository staff only - Requires a PDF viewer. Download (2323Kb) |
Official URL: https://doi.org/10.1021/acs.chemmater.9b04512
Abstract
By tuning the tolerance factor, t, of the Ruddlesden–Popper oxide Ca2MnO4 through isovalent substitutions, we show that the uniaxial coefficient of linear thermal expansion (CLTE) of these systems can be systematically changed through large negative to positive values. High-resolution X-ray diffraction measurements show that the magnitude of uniaxial negative thermal expansion (NTE) increases as t decreases across the stability window of the NTE phase. Transitions to phases with positive thermal expansion (PTE) are found to occur at both the high-t and low-t limits of stability. First-principles calculations demonstrate that reducing t enhances the contribution to thermal expansion from the lowest frequency phonons, which have the characteristics of octahedral tilts and have negative mode Grüneisen parameter components along the NTE axis. By tuning t to the lower edge of the NTE phase stability window, we are hence able to maximize the amplitudes of these vibrations and thereby maximize NTE with a CLTE of −8.1 ppm/K at 125 K. We also illustrate, at the other end of the phase diagram, that an enhancement in compliance of these materials associated with the rotational instability provides another mechanism by which NTE could be yet further enhanced in this and related systems.
| Item Type: | Journal Article | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Subjects: | Q Science > QE Geology T Technology > TA Engineering (General). Civil engineering (General) |
|||||||||||||||||||||
| Divisions: | Faculty of Science, Engineering and Medicine > Science > Chemistry | |||||||||||||||||||||
| Library of Congress Subject Headings (LCSH): | Expansion (Heat) , Materials at high temperature, Materials -- Thermal properties, Perovskite , Perovskite -- Thermal properties | |||||||||||||||||||||
| Journal or Publication Title: | Chemistry of Materials | |||||||||||||||||||||
| Publisher: | American Chemical Society | |||||||||||||||||||||
| ISSN: | 0897-4756 | |||||||||||||||||||||
| Official Date: | 14 January 2020 | |||||||||||||||||||||
| Dates: |
|
|||||||||||||||||||||
| Volume: | 32 | |||||||||||||||||||||
| Number: | 1 | |||||||||||||||||||||
| Page Range: | pp. 605-610 | |||||||||||||||||||||
| DOI: | 10.1021/acs.chemmater.9b04512 | |||||||||||||||||||||
| Status: | Peer Reviewed | |||||||||||||||||||||
| Publication Status: | Published | |||||||||||||||||||||
| Reuse Statement (publisher, data, author rights): | “This document is the Accepted Manuscript version of a Published Work that appeared in final form in Chemistry of Materials, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see Work, see http://pubs.acs.org/page/policy/articlesonrequest/index.html].” | |||||||||||||||||||||
| Access rights to Published version: | Restricted or Subscription Access | |||||||||||||||||||||
| Date of first compliant deposit: | 14 January 2020 | |||||||||||||||||||||
| RIOXX Funder/Project Grant: |
|
Request changes or add full text files to a record
Repository staff actions (login required)
 |
View Item |
