Hostname: page-component-7b7567c8c-7pwfn Total loading time: 0 Render date: 2026-11-15T02:33:51.954Z Has data issue: false hasContentIssue false

Cathodoluminescence microcharacterization of point defects in α-quartz

Published online by Cambridge University Press:  05 July 2018

M. A. Stevens-Kalceff*
Affiliation:
School of Physics and Electron Microscope Unit, University of New South Wales, Sydney NSW 2052, Australia

Abstract

Cathodoluminescence (CL) spectroscopy in an SEM has been used to investigate the point defect structure of clear natural α-quartz at 295 K. Cathodoluminescence processes and experimental factors that influence the CL spectra from α-quartz are investigated. Electron irradiation may induce changes in the average local crystal micro structure of quartz, locally transforming it to a less dense, amorphized state. The observed CL emissions are identified with a range of native and impurity defect centres including: interstitial molecular O at 0.968 eV; a charge-compensated substitutional Fe3+ impurity centre at —1.65 eV; a non-bridging oxygen hole centre (NBOHC) at 1.9 eV; an NBOHC with OH~ precursor at 1.95 eV; an NBOHC with a non-bridging impurity (e.g. Li+, Na+ or K+) precursor at — 1.9 eV; a radiative recombination of the self-trapped exciton (STE) associated with an E' centre in electron-irradiation-amorphized quartz at 2.3 eV; a radiative recombination of the STE associated with the E1' centre in α-quartz at 2.7 eV; a charge-compensated-substitutional Al3+ impurity centre at 3.3 eV; and a neutral relaxed O vacancy at 4.3 eV. In addition, unresolved contributions from O-deficient defects in electron-irradiation-amorphized SiO2 are likely at —2.7 and 4.3 eV.

Information

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable