EFFECT OF PROTONATION OF NITROGEN-CONTAINING ORGANIC-MOLECULES ON THE REACTIVITY TOWARD POSITRONIUM

Positron lifetime parameters in aqueous or methanol solutions of pyrimidine, quinoline, and quinoxaline were determined with and without hydrochloric acid. By analyzing the data, the Ps reaction rate constant k and the Ps inhibition coefficient σ of free molecules and protonated cations were determined. The protonation of these molecules enhances k and σ considerably. The qualitative considerations suggest that the complex formation reaction between Ps and the protonated cations is responsible for the increase of k by protonation. © 1979, American Chemical Society. All rights reserved.