✦ LIBER ✦

Resonance Raman study of carotenoid cation radicals

✍ Scribed by A.S. Jeevarajan; L.D. Kispert; G. Chumanov; C. Zhou; T.M. Cotton

Publisher: Elsevier Science
Year: 1996
Tongue: English
Weight: 608 KB
Volume: 259
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(96)00781-6

No coin nor oath required. For personal study only.

✦ Synopsis

The resonance Raman (RR) spectra of the neutral and the cation radical of 8'-apo-/3-caroten-8'-al (I), 7',7'-dicyano-7'apo-/3-carotene (II) and canthaxanthin (III) were measured using 752.6 nm laser excitation. Optical and RR spectra of the electrochemically prepared cation radicals of I-III were measured in situ at different time intervals during the electrolysis. The RR spectra of the cation radicals are considerably different from those of the neutral species. The frequencies of the C=C stretching vibrations are decreased by 30-40 cm-t, whereas those of C-C stretching vibrations are increased by 15-30 cm-~. These results suggest delocalization of the unpaired electron density throughout the entire carbon backbone which is consistent with our previous EPR and ENDOR results.

📜 SIMILAR VOLUMES

Resonance Raman studies of phenylcyclopr

Resonance Raman studies of phenylcyclopropane radical cations

✍ Jerry T. Godbout; Han Zuilhof; Gary Heim; Ian R. Gould; Joshua L. Goodman; Josep 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 151 KB 👁 2 views

Resonance Raman spectra of the radical cations of phenylcyclopropane and trans-1-phenyl-2-methylcyclopropane are reported. A near-UV pump pulse excites a photosensitizer which oxidizes the species of interest, and a visible probe pulse delayed by 35 ns obtains the spectrum of the radical ion. The tr

An ENDOR study of carotenoid cation radi

An ENDOR study of carotenoid cation radicals on silica—alumina solid supports

✍ A.S. Jeevarajan; L.D. Kispert; L. Piekara-Sady 📂 Article 📅 1993 🏛 Elsevier Science 🌐 English ⚖ 500 KB

The cation radicals of canthaxanthin, B-carotene and S'-apo+camten-8'-al were chemically prepared on activated sihca-alumina solid supports. An ENDOR study of these cation radicals revealed the hypertine coupling constants of the methyl protons and indicated a carotenoiddependent orientation of the

The resonance Raman spectrum of the anil

The resonance Raman spectrum of the aniline radical cation

✍ G.N.R. Tripathi; Robert H. Schuler 📂 Article 📅 1984 🏛 Elsevier Science 🌐 English ⚖ 338 KB

Free radical studies by resonance Raman

Free radical studies by resonance Raman spectroscopy: Photochemically generated para-substituted aniline cation radicals

✍ K. P. J. Williams; R. E. Hester 📂 Article 📅 1981 🏛 John Wiley and Sons 🌐 English ⚖ 378 KB

Resonance Raman study of the benzyl radi

Resonance Raman study of the benzyl radical

✍ Frans W. Langkilde; Krzysztof Bajdor; Robert Wilbrandt 📂 Article 📅 1992 🏛 Elsevier Science 🌐 English ⚖ 674 KB

Resonance Raman of viologen radicals

✍ P.C. Lee; K. Schmidt; S. Gordon; D. Meisel 📂 Article 📅 1981 🏛 Elsevier Science 🌐 English ⚖ 582 KB

The resonance Raman effect of the radical cation of 4,4'-bipyridinium salts was recorded and correlated with the Raman .vectra of the parent molecules. The radxais were produced either chemically or radiolytically. The correlation between the radical cation and its parent salt is then compared with