Dynamic nuclear polarization using polychlorotriphenylmethyl radicals reveals supramolecular polarization transfer effects

Abstract

Polychlorinated trityl radicals (see structure: C black, Cl green, Na gray, O red) used for dynamic nuclear polarization (DNP) showed a new transfer mechanism involving quadrupolar chlorine nuclei. The observation of positive or negative enhancements, depending on the substrate, highlights the supramolecular character of the initial polarization‐transfer process