Home Rietveld refinement of incommensurate low tridymite
Article
Licensed
Unlicensed Requires Authentication

Rietveld refinement of incommensurate low tridymite

  • H. A. Graetsch
Published/Copyright: September 25, 2009

Abstract

The incommensurate modification of SiO2 low-tridymite was refined in the 3 + 1 dimensional superspace group Cc(α0γ) 0 at 295 and 325 K from X-ray powder diffraction data. The displacive modulation mainly consists of tiltings of rigid SiO4/2 tetrahedra with the wave vector r = 0.656a* – 0.496c* (dimensions of the average cell: a = 5.005 Å, b = 8.598 Å, c = 8.213 Å and β = 91.50°). The largest amplitude is ca. 0.6 Å for oxygen and ca. 0.3 Å for silicon. Wave vector and amplitudes of the displacive modulation functions vary only very little with increasing temperature.

:
Published Online: 2009-9-25
Published in Print: 2003-8-1

© 2003 Oldenbourg Wissenschaftsverlag GmbH

Downloaded on 10.9.2025 from https://www.degruyterbrill.com/document/doi/10.1524/zkri.218.8.531.20687/html
Scroll to top button