title: The Vitamin E Radical Probed by Anion Photoelectron Imaging.
abstract: The biological antioxidant activity of vitamin E has been related to the stability of the tocopheroxyl radical. Using anion photoelectron imaging and electronic structure calculations, the four tocopheroxyl components of vitamin E have been studied in the gas phase and have yielded the adiabatic electron affinity of the α-, β/γ-, and δ-tocopheroxyl radicals. Using these values, the bond dissociation enthalpy of the O-H bond of tocopherol has been estimated and is consistent with previous studies and with the trends in biological activity. Differences in the photoelectron angular distributions have been interpreted to result from changes in the symmetry of the molecular orbitals from which the electron was detached.
authors.affiliation: Department of Chemistry, Durham University , Durham DH1 3LE, United Kingdom.
authors.forename: Cate S
authors.initials: CS
authors.lastname: Anstöter
authors.affiliation: Department of Chemistry, Durham University , Durham DH1 3LE, United Kingdom.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: West
authors.affiliation: Department of Chemistry, Durham University , Durham DH1 3LE, United Kingdom.
authors.forename: James N
authors.initials: JN
authors.lastname: Bull
authors.affiliation: Department of Chemistry, Durham University , Durham DH1 3LE, United Kingdom.
authors.forename: Jan R R
authors.initials: JR
authors.lastname: Verlet
mesh_terms: D005609:Free Radicals / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D011789:Quantum Theory; D013816:Thermodynamics; D014810:Vitamin E / Q000737:chemistry*
chemical_list: D005609:Free Radicals; C066323:tocopheroxy radical; D014810:Vitamin E