Infrared and EPR Spectroscopic Studies of 2-C2H2F and 1-C2H2F Radicals Isolated in Solid Argon

✍ Scribed by I.U. Goldschleger; A.V. Akimov; E.Ya. Misochko; C.A. Wight

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 201 KB
• Volume: 205
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2000.8266

✦ Synopsis

2-fluorovinyl radicals were generated in solid argon by solid-state chemical reactions of mobile F atoms with acetylene and its deuterated analogues. Highly resolved EPR spectra of the stabilized radicals CHF&dbond(*)CH, CDF&dbond(*)CD, CHF&dbond(*)CD, and CDF&dbond(*)CH were obtained for the first time. The observed spectra were assigned to cis-2-fluorovinyl radical based on excellent agreement between the measured (a(F) = 6.50, a(betaH) = 3.86, a(alphaH) = 0.25 mT) hyperfine constants and those calculated using density functional (B3LYP) theory. Analogous experiments carried out using infrared spectroscopy yielded a complete assignment of the vibrational frequencies. An unusual reversible photochemical conversion is observed in which cis-2-fluorovinyl radicals can be partially converted to 1-fluorovinyl radicals by pulsed laser photolysis at 532 nm. Photolysis at 355 nm converts 1-fluorovinyl back to cis-2-fluorovinyl. High-resolution EPR and infrared spectra of 1-fluorovinyl were obtained for the first time. The measured hyperfine constants (a(F) = 13.71, a(H1) = 4.21, a(H2) = 1.16 mT) are in good agreement with calculated values. Copyright 2001 Academic Press.