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Updated: Jul 9, 2026
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Observation of long-range compositional fluctuations in glasses: implications for atomic and electronic structure
Nan Jiang1, Jianrong Qiu, C J Humphreys
1Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1504, USA. nan.jiang@asu.edu
Micron (Oxford, England : 1993)
|December 7, 2007
Summary
Long-range compositional fluctuations in glasses were experimentally observed using advanced spectroscopy. These findings reveal insights into electronic structure and stoichiometry-driven variations in glass materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid-State Chemistry
Background:
- Glasses exhibit complex atomic arrangements.
- Understanding compositional variations is crucial for material properties.
- Previous studies lacked direct evidence of long-range fluctuations.
Purpose of the Study:
- To provide experimental evidence for long-range compositional fluctuations in glasses.
- To analyze the implications of these fluctuations on electronic structure.
- To investigate stoichiometry-induced structural variations.
Main Methods:
- Utilized inner shell near-edge absorption spectroscopy with a 50nm diameter probe.
- Examined the spatial dependence of absorption spectra.
- Performed comparisons with spectra from compositionally equivalent crystals.
- Employed multiple-scattering calculations including core-hole effects.
Main Results:
- Direct experimental evidence for long-range compositional fluctuations in glasses was obtained.
- Spectroscopy revealed sensitivity to angular and distance correlations in bonding.
- Analysis indicated implications for electronic structure and stoichiometry.
Conclusions:
- Long-range compositional fluctuations are a key feature of glass structures.
- These fluctuations significantly influence the electronic and structural properties of glasses.
- The applied spectroscopic technique is effective for probing nanoscale compositional variations.
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