IR SPECTRA OF ANION-RADICALS OF AROMATIC MONO-NITRILES, AND ELECTRON TRANSITIONS BETWEEN ANION RADICALS AND NEUTRAL MOLECULES

The infrared spectra (680-2500 cm-1) are measured of the anion-radicals (AR) of benzonitrile, 1- and 2-naphthalenecarbonitriles, 9-phenanthrenecarbonitrile, 4-biphenylcarbonitrile, 1-pynitriles, 9-phenanthrenecarbonitrile, 4-biphenylcarbonitrile, 1-pyrenecarbonitrile and 9-anthracenecarbonitrile, obtained on treating the initial nitriles with metallic potassium in tetrahydrofuran. The formation of the AR leads to a decrease of the out-of-plane C-H frequencies in the region 700-800 cm-1. The nitrile frequencies of the AR is observed in the region 2080 to 2125 cm-1, which is in agreement with the decreased order of the C≡N bond (HMO). The IR-Spectra in the interval 2000 to 2250 cm-1 are used in the study of the electron transitions between the AR and the nitrile molecules. The electron transitions in the examined nitriles are in general agreement with the energies of the first antibonding orbitals, calculated by HMO. © 1969 Springer-Verlag.