Stabilization and isomerization of radical cations generated by fast electron irradiation of unsaturated organic molecules in a solid argon matrix

Matrix isolation EPR spectroscopy was used to study the fate of “hot” unsaturated radical cations produced by fast electron irradiation in solid argon. It was found that the radical cations of cis-2-butene, trans-2-butene and ethyl vinyl ether resulting from highly exothermic hole transfer (excess energy>6 eV) underwent effective relaxation in an argon matrix. 1-Butene radical cation exhibits isomerization to cis-2-butene radical cation. The role of molecular structure of organic radical cations in excess energy relaxation is discussed.