Polychlorinated trityl radicals for dynamic nuclear polarization: the role of chlorine nuclei.
Polychlorinated trityl radicals bearing carboxylate substituents are water soluble persistent radicals that can be used for dynamic nuclear polarization. In contrast to other trityl radicals, the polarization mechanism differs from the classical solid effect. DFT calculations performed to rationalize this behaviour support the hypothesis that polarization is transferred from the unpaired electron to chlorine nuclei and from these to carbon by spin diffusion. The marked differences observed between neutral and anionic forms of the radical will be discussed.
Paniagua
Juan Carlos
JC
Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain.
Mugnaini
Verónica
V
Gabellieri
Cristina
C
Feliz
Miguel
M
Roques
Nans
N
Veciana
Jaume
J
Pons
Miquel
M
D002713:Chlorine / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011080:Polychloroterphenyl Compounds / Q000737:chemistry*
D005609:Free Radicals; D011080:Polychloroterphenyl Compounds; D002713:Chlorine