Direct observation of geminate recombination within photochemically produced ion pairs in polar solutions

✍ Scribed by D.M. Goodall; N. Orbach; M. Ottolenghi

• Publisher: Elsevier Science
• Year: 1974
• Tongue: English
• Weight: 365 KB
• Volume: 26
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(74)89050-0

✦ Synopsis

Pulsed laser excitation of pyrene @'j/N, N-diethylaniline (DEA) solutions in methanol at low temperatures leads to the generation of the P-and DEA+ radical ions. A fast initial decay of the ions (T served and is attributed to geminate recombination within the initially formed (2P-__ '3 = 37 nsec at -4O'C) is ob-DEk+) ion pair. The quenching of tP* by DEA is also associated with substantial intersystem crossing, yieldingJP*. The data rule out both gemiate and non-geminate (homogeneous) ionic recombinations as sources for the initial yield of 3p*. in keeping with a prompt triplet formation mechanism.