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Updated: Jun 20, 2026

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging
Published on: September 2, 2016
Internally referenced diffusion coefficient-formula weight (D-FW) analysis of 31P diffusion-ordered NMR spectroscopy
Gerald Kagan1, Weibin Li, Russell Hopson
1Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
Researchers developed phosphorus-31 diffusion ordered spectroscopy (31P DOSY) NMR with diffusion coefficient-formula weight (D-FW) analysis. This method successfully determined the molecular weight of organolithium compounds, expanding its use for solution structure studies.
Area of Science:
- Analytical Chemistry
- Organic Chemistry
- Nuclear Magnetic Resonance Spectroscopy
Background:
- Diffusion Ordered Spectroscopy (DOSY) is a powerful NMR technique for separating mixtures.
- Integrating diffusion coefficient with formula weight (D-FW) analysis allows for molecular weight determination.
- Previous D-FW analysis has limitations in studying phosphorus-containing compounds.
Purpose of the Study:
- To develop and validate a (31)P DOSY NMR method combined with D-FW analysis.
- To establish the feasibility of using this technique for determining the molecular weight of organophosphorus compounds.
- To expand the applicability of DOSY D-FW analysis to a broader range of chemical structures.
Main Methods:
- Utilized phosphorus-31 (31P) Nuclear Magnetic Resonance (NMR) spectroscopy.
- Employed Diffusion Ordered Spectroscopy (DOSY) to measure diffusion coefficients.
- Integrated diffusion coefficient-formula weight (D-FW) analysis using trialkyl phosphine internal references in a model system.
Main Results:
- Successfully established the (31)P DOSY NMR with D-FW analysis method.
- Demonstrated the ability to accurately determine the molecular weight of a phosphorous-containing organolithium compound.
- Confirmed the feasibility and reliability of the developed (31)P DOSY D-FW approach.
Conclusions:
- The developed (31)P DOSY NMR with D-FW analysis is a viable technique for molecular weight determination.
- This method significantly broadens the scope of DOSY D-FW analysis.
- It offers a new tool for solution structure elucidation of diverse organophosphorus compounds.
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