Microhydration and the Enhanced Acidity of Free Radicals

Molecules

JohnC. Walton¹ 

[1] EaStCHEM School of Chemistry, University of St. Andrews, St. Andrews KY16 9ST, UK;

关键词: free radicals;    acidity;    DFT computations;    hydration;   

DOI  :  10.3390/molecules23020423

来源: DOAJ

【 摘 要 】

Recent theoretical research employing a continuum solvent model predicted that radical centers would enhance the acidity (RED-shift) of certain proton-donor molecules. Microhydration studies employing a DFT method are reported here with the aim of establishing the effect of the solvent micro-structure on the acidity of radicals with and without RED-shifts. Microhydration cluster structures were obtained for carboxyl, carboxy-ethynyl, carboxy-methyl, and hydroperoxyl radicals. The numbers of water molecules needed to induce spontaneous ionization were determined. The hydration clusters formed primarily round the CO2 units of the carboxylate-containing radicals. Only 4 or 5 water molecules were needed to induce ionization of carboxyl and carboxy-ethynyl radicals, thus corroborating their large RED-shifts.

【 授权许可】

Unknown