Notwithstanding the facile occurrence of one-electron oxidation in a-tocopherol and its acetate (Tom and TOAc, respectively), and despite the remarkable stability, under appropriate conditions, of the oxidation products (TOH.+, TO center dot and TOAC), their spectroscopic characterization is in an unsatisfactory state, calling for a fresh attempt to acquire reliable data. A new, model-free method is developed for analyzing time-resolved spectra showing the progress of the reaction TOH + R-center dot TO + RH, where R-center dot is a stable free radical. The resulting absorption coefficients of TO. in dichloromethane and hexane are M severe disagreement with some recent values derived from stopped-flow spectrophotometry. The discrepancy is traced to the imposition of boundary conditions that do not take proper account of the dead time of the apparatus; when multiplied by a factor or two, the stopped-flow data all mostly in the range epsilon (7.5 +/-0.5) x 10(3) M-1 cm conforming with the results of this study and the values found by Boguth and Niemann in 1969. Absorption spectra of the radical cations produced (electro)chemically are found to be reliable only in the visible region. Incomplete conversion of the parent compound to the radical cation, an obstacle to the determination of absorption coefficients from electrochemical studies, is circumvented by combining EPR and optical spectroscopy. The absorption coefficients of TOH+ and TOAC(center dot+) determined in tins manner, are found to be, respectively, 1.6 x 10(4) and 1.3 x 10(4) M-1 cm in accord with the values found first through similar means.