Excited state relaxation of Cr(III) in oxygen environments

✍ Scribed by Leslie S. Forster

• Book ID: 104010621
• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 198 KB
• Volume: 248
• Category: Article
• ISSN: 0010-8545
• DOI: 10.1016/j.ccr.2003.10.014

✦ Synopsis

The emission spectra and excited state decay characteristics of Cr 3+ ions in oxide crystals and glasses and molecular complexes are reviewed. The relevant species can be described as CrO 6 and both narrow 2 E ⇒ 4 A 2 phosphorescence and broadband 4 T 2 ⇒ 4 A 2 fluorescence are observed with intensities and lifetimes that depend on the disposition of the excited levels and the temperature. A unified model that relates the emission in the several environments is described. A kinetic analysis is applied to extract individual rate constants and to determine the origin of the thermal quenching. Kinetic limits on 2 E ⇒ 4 T 2 back-transfer are explored.