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Updated: Mar 21, 2026
06:48
Fluid-cell Raman Spectroscopy for operando Studies of Reaction and Transport Phenomena during Silicate Glass Corrosion
Published on: May 9, 2025
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Modifier cation effects on (29)Si nuclear shielding anisotropies in silicate glasses
Jay H Baltisberger1, Pierre Florian2, Eric G Keeler3
1Division of Natural Science, Mathematics, and Nursing, Berea College, Berea, KY 40403, United States.
Summary
This study reveals a linear relationship between silicon-29 nuclear shielding anisotropy and silicon-oxygen bond length in silicate glasses. Paramagnetic doping significantly speeds up 2D NMR experiments for glass structure analysis.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Nuclear Magnetic Resonance Spectroscopy
Background:
- Silicate glasses are amorphous materials with complex structures.
- Understanding the local atomic arrangements in glasses is crucial for tailoring their properties.
- Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful tool for probing glass structures.
Purpose of the Study:
- To investigate the variations in silicon-29 ((29)Si) nuclear shielding tensor parameters in various alkali and alkaline earth silicate glasses.
- To establish structure-property relationships based on (29)Si NMR data.
- To develop faster 2D NMR methods for glass analysis.
Main Methods:
- Utilized natural abundance (29)Si two-dimensional magic-angle flipping (MAF) NMR experiments.
- Analyzed seven different alkali and alkaline earth silicate glass compositions.
- Employed Cu(2+) as a paramagnetic dopant and echo train acquisition to accelerate experiments.
Main Results:
- A linear dependence was observed between (29)Si nuclear shielding anisotropy in Q((3)) sites and the Si-non-bridging oxygen bond length.
- This bond length is influenced by cation potential and modifier cation coordination.
- Experiment time for (29)Si 2D NMR measurements was reduced by two orders of magnitude.
Conclusions:
- The study establishes a correlation between local structure (bond length) and NMR parameters in silicate glasses.
- Paramagnetic doping and advanced NMR techniques significantly enhance the efficiency of glass structure characterization.
- These findings facilitate higher throughput studies of glass network structures.
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