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Title: Phase behaviour, thermal expansion and compressibility of SnMo 2 O 8

Abstract

The phase behaviour and thermoelastic properties of SnMo2O8, derived from variable temperature and pressure synchrotron powder diffraction data, are reported. SnMo2O8 is a member of the AM2O8 family of negative thermal expansion (NTE) materials, but unexpectedly, has positive thermal expansion. Over the P-T space explored (298–513 K, ambient to 310 MPa) four different forms of SnMo2O8 are observed: α, β, γ and γ'. The γ to β transition is temperature-, pressure-, and time-dependent. SnMo2O8 is a much softer material (α and γ form have BT = 29 and 26 GPa at 298 K) than other members of the AM2O8 family. Counter-intuitively, its high temperature β phase becomes stiffer with increasing temperature (BT ~36 GPa at 490 K). The pressure dependence of the thermal expansion for each phase is reported.

Authors:
; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
DOE - BASIC ENERGY SCIENCESFOREIGN
OSTI Identifier:
1418057
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 258; Journal Issue: C
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Araujo, Luiza R., Gallington, Leighanne C., Wilkinson, Angus P., and Evans, John S. O. Phase behaviour, thermal expansion and compressibility of SnMo 2 O 8. United States: N. p., 2018. Web. doi:10.1016/j.jssc.2017.08.040.
Araujo, Luiza R., Gallington, Leighanne C., Wilkinson, Angus P., & Evans, John S. O. Phase behaviour, thermal expansion and compressibility of SnMo 2 O 8. United States. doi:10.1016/j.jssc.2017.08.040.
Araujo, Luiza R., Gallington, Leighanne C., Wilkinson, Angus P., and Evans, John S. O. 2018. "Phase behaviour, thermal expansion and compressibility of SnMo 2 O 8". United States. doi:10.1016/j.jssc.2017.08.040.
@article{osti_1418057,
title = {Phase behaviour, thermal expansion and compressibility of SnMo 2 O 8},
author = {Araujo, Luiza R. and Gallington, Leighanne C. and Wilkinson, Angus P. and Evans, John S. O.},
abstractNote = {The phase behaviour and thermoelastic properties of SnMo2O8, derived from variable temperature and pressure synchrotron powder diffraction data, are reported. SnMo2O8 is a member of the AM2O8 family of negative thermal expansion (NTE) materials, but unexpectedly, has positive thermal expansion. Over the P-T space explored (298–513 K, ambient to 310 MPa) four different forms of SnMo2O8 are observed: α, β, γ and γ'. The γ to β transition is temperature-, pressure-, and time-dependent. SnMo2O8 is a much softer material (α and γ form have BT = 29 and 26 GPa at 298 K) than other members of the AM2O8 family. Counter-intuitively, its high temperature β phase becomes stiffer with increasing temperature (BT ~36 GPa at 490 K). The pressure dependence of the thermal expansion for each phase is reported.},
doi = {10.1016/j.jssc.2017.08.040},
journal = {Journal of Solid State Chemistry},
number = C,
volume = 258,
place = {United States},
year = 2018,
month = 2
}
  • No abstract prepared.
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