Hydrogen and minor element incorporation in synthetic rutile

GD Bromiley*, N Hilairet

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

The solubility and incorporation mechanisms of H and various trivalent and divalent cations in synthetic rutile have been investigated. Experiments performed using different bulk Fe2O3 contents demonstrate that Fe3+ substitutes onto the main Ti site, charge-balanced by oxygen vacancies. Under more reducing conditions in Fe-poor systems, the concentration of Ti interstitials in rutile is increased, resulting in a decrease in H solubility. Variation in the solubility of different oxides in rutile as a function of ionic radius implies substitution onto the main Ti site, probably charge-balanced by oxygen vacancies. To a lesser degree, substitution of trivalent and divalent cations is locally charge-balanced by H incorporation. Variation in OH-stretching frequencies in infrared spectra as a function of composition implies that octahedral defects and structurally-incorporated H are coupled. However, in all samples, some of the H is also decoupled from substitutional impurities, as is evident from an OH-absorption band at 3279 cm(-1). This band corresponds to the main OH band seen in spectra of many natural rutiles, implying that in most rutiles, H defects are decoupled from substitutional defects.

Original languageEnglish
Pages (from-to)345-358
Number of pages14
JournalMineralogical Magazine
Volume69
Issue number3
DOIs
Publication statusPublished - Jun 2005
EventMeeting on Proton-Mediated Interactionsl in Minerals - Manchester, United Kingdom
Duration: 1 Sep 2004 → …

Keywords

  • rutile
  • hydrogen
  • substitution
  • solubility
  • spectroscopy
  • STRETCHING FREQUENCIES
  • GARNET RIDGE
  • UPPER-MANTLE
  • ABSORPTION
  • HYDROXYL
  • MINERALS
  • SUBSTITUTION
  • SOLUBILITY
  • CHEMISTRY
  • DEFECTS

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