Abstract
The properties of ceramic materials are strongly influenced by the presence of ultradilute impurities (dopants). Near-edge X-ray absorption fine structure (NEXAFS) measurements using third-generation synchotron sources can be used to identify ultradilute dopants, provided that a good theoretical tool is available to interpret the spectra. Here, we use NEXAFS analysis and first-principles calculations to study the local environments of Ga dopants at levels of 10 p.p.m in otherwise high-purity MgO. This analysis suggests that the extra charge associated with substitutional Ga on a Mg site is compensated by the formation of a Mg vacancy. This defect model is then confirmed by positron lifetime measurements and planewave pseudopotential calculations. This powerful combination of techniques should provide a general method of identifying the defect states of ultradilute dopants in ceramics.
Original language | English |
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Pages (from-to) | 541-545 |
Number of pages | 5 |
Journal | Nature Materials |
Volume | 2 |
Issue number | 8 |
DOIs | |
Publication status | Published - Aug 2003 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- Chemistry(all)
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering