Identification of ultradilute dopants in ceramics
Source abstract
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 plane-wave pseudopotential calculations. This powerful combination of techniques should provide a general method of identifying the defect states of ultradilute dopants in ceramics.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Muon and positron interactions and applications · Rare-earth and actinide compounds · X-ray Spectroscopy and Fluorescence Analysis
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (18)
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