Reduction of tetranitromethane by electronically excited aromatics in acetonitrile: Spectra and molar absorption coefficients of radical cations of anthracene, phenanthrene and pyrene

摘要

Room temperature absorption spectra of the long-lived transient species produced by photolysing solutions containing tetranitromethane (TNM) or a TNM/arene mixture have been recorded with a multi-channel spectrophotometer, capable of mu s time resolution and covering a wide spectral range (200-1010 nm). The arene was anthracene (A), naphthalene (N), phenanthrene (Phi), or pyrene (P). In methanol, A(.+), N.+ and Phi(.+) disappear within the available time resolution, but all four cations live for tens or hundreds of mu s in acetonitrile; the molar absorption coefficients of A(.+), Phi(.+) and P.+ in the latter solvent match those of the respective anions in tetrahydrofuran. (c) 2006 Elsevier B.V. All rights reserved.