Physics and Chemistry of Minerals

, Volume 36, Issue 3, pp 171–181

X-ray Raman scattering for structural investigation of silica/silicate minerals

Original Paper

DOI: 10.1007/s00269-008-0267-x

Cite this article as:
Fukui, H., Kanzaki, M., Hiraoka, N. et al. Phys Chem Minerals (2009) 36: 171. doi:10.1007/s00269-008-0267-x

Abstract

We have performed X-ray Raman scattering (XRS) measurements on the oxygen K and silicon L absorption edges of four silica minerals: α-quartz, α-cristobalite, coesite, and stishovite. We have also calculated the partial electron densities of states (DOSs) and compared these with the XRS spectra. This study demonstrates that the short-range structure around the atom of interest strongly influences the XRS spectral features. Importantly, the oxygen K-edge XRS spectra are found to reflect the p-orbital DOS while the silicon L-edge spectra reflect the s- and d-orbital DOSs, even when a product of a momentum transfer and a mean radius of a electron orbit (1s for oxygen and 2p for silicon), Qr, is close to or larger than unity. Building on this, calculations of the partial DOSs for other silica phases are presented, including ultra-high-pressure phases, which provide a good reference for further XRS study of silica and silicate minerals. XRS measurements should be performed on not only either of oxygen or silicon but also on many kinds of constituent elements to reveal the structural change of glasses/melts of silicates under extreme conditions.

Keywords

X-ray Raman scatteringSiO2 polymorphsShort-range structureIntermediate structureElectronic structure

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • H. Fukui
    • 1
    • 3
  • M. Kanzaki
    • 1
  • N. Hiraoka
    • 2
  • Y. Q. Cai
    • 2
    • 4
  1. 1.Institute of Study for the Earth’s InteriorOkayama UniversityMisasaJapan
  2. 2.National Synchrotron Radiation Research CenterHsinchuTaiwan
  3. 3.Materials Dynamics LaboratorySPring-8/Harima Institute, RIKENSayoJapan
  4. 4.National Synchrotron Light Source IIBrookhaven National LaboratoryUptonUSA