Time-resolved fluorescence spectra using time-correlated photon counting: Picosecond fluorescence in aqueous solutions of Cr(III) complexes at room temperature
✍ Scribed by Gail Rojas; Douglas Magde
- Publisher
- Elsevier Science
- Year
- 1983
- Tongue
- English
- Weight
- 519 KB
- Volume
- 102
- Category
- Article
- ISSN
- 0009-2614
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✦ Synopsis
A new procedure for measuring time-resolved emission spectra has been implemented. This technique has subnanosecond time resolution combined with the sensitivity and dynamic range needed 10 cope with estremely weak luminescence. Using this method the emissions of Cr(NH3)2 (NCS); and Cr(NCS$ in aqueous solution nt room temperature have each been analyzed into two components. The fast component has a broad spectrum and is assigned to prompt fluorescence with lifetime below 100 ps. The slow component is dominated by phosphorescence but may include some delayed fluorescence_ The phosphorescence lifetime is 5.5 + 0.5 ns in Cr(NH& (NCS)i and 1.65 k 0.1 ns in Cr(NC&. Order of magnitude estimates have been derived for other photophysical parameters.