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Published on: September 5, 2014
Solvents showing the external heavy atom effect in phosphorimetry
1Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, U.S.A.
Talanta
|April 1, 1970
Summary
Heavy atom solvents enhance phosphorimetry. Bromine-containing solvents offer the best balance of ultraviolet transmission and spin-orbit coupling for improved phosphorescence intensity and longer lifetimes.
Area of Science:
- Analytical Chemistry
- Photochemistry
Background:
- The external heavy atom effect is crucial for enhancing phosphorimetry.
- Previous studies primarily used iodine-containing solvents, yielding inconsistent results.
- Ultraviolet transmission properties of solvents may influence enhancement efficiency.
Purpose of the Study:
- To evaluate chlorine-, bromine-, and iodine-containing solvents for the external heavy atom effect in phosphorimetry.
- To investigate the impact of different heavy atom solvents on phosphorescence and fluorescence intensities.
- To identify optimal solvent systems for routine phosphorimetric analysis.
Main Methods:
- Systematic examination of ten heavy atom-containing solvents.
- Comparative analysis of phosphorescence and fluorescence intensities.
- Measurement of excited state lifetimes in different solvent systems.
Main Results:
- Chlorine- and bromine-containing solvents demonstrated significant improvements in phosphorimetric enhancement.
- These solvents also exhibited slightly longer excited state lifetimes compared to iodine-containing systems.
- Bromine-containing solvents provided the best combination of ultraviolet transmission and spin-orbit coupling.
Conclusions:
- Solvent choice significantly impacts external heavy atom effect efficiency in phosphorimetry.
- Bromine-based solvent systems present a favorable balance for enhanced analytical performance.
- Further research into solvent optimization can refine phosphorimetric techniques.
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