Tripoliti, EK;
Thomson, AR;
Dobson, DP;
Schofield, PF;
Wood, IG;
(2025)
The thermal expansion of the clinopyroxene and garnet polymorphs of Na2MgSi5O12 determined by X-ray powder diffraction.
Physics and Chemistry of Minerals
, 52
(2)
, Article 14. 10.1007/s00269-025-01315-x.
Preview |
Text
Wood_s00269-025-01315-x.pdf Download (2MB) | Preview |
Abstract
The temperature dependence of the unit-cell parameters of synthetic Na(Mg0.5Si0.5)Si2O6 clinopyroxene and Na2MgSi5O12 garnet were measured, at atmospheric pressure, using X-ray powder difraction, from 40 K up to their decomposition temperatures (673 K and 793 K respectively). At 300 K the cell parameters were found to be: (i) a=9.4073(3) Å, b=8.6487(3) Å, c=5.2685(2) Å, β=108.113(2)°, V=407.41(3) Å3 and ρ=3.286 g/cm3 , for Na(Mg0.5Si0.5)Si2O6 pyroxene in space-group P2/n with Z=4 and (ii) a=11.4155(7) Å, V=1487.61(5) Å3 and ρ=3.561 g/cm3 for Na2MgSi5O12 garnet in space-group Ia3d with Z=8. The thermal expansion tensors have been calculated and analysis of the lattice parameters in terms of a GrüneisenDebye model is used to estimate the Debye temperature and the incompressibility of the two materials at ambient pressure.
| Type: | Article |
|---|---|
| Title: | The thermal expansion of the clinopyroxene and garnet polymorphs of Na2MgSi5O12 determined by X-ray powder diffraction |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1007/s00269-025-01315-x |
| Publisher version: | https://doi.org/10.1007/s00269-025-01315-x |
| Language: | English |
| Additional information: | This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. |
| Keywords: | Sodium pyroxene (Na(Mg0.5Si0.5)Si2O6); Sodium garnet (Na2MgSi5O12); Thermal expansion; X-ray powder difraction |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10207368 |
Archive Staff Only
 |
View Item |
