EPR studies on fluorocarbon microspheres. Dynamic polarization of fluorine nuclei and adsorbed He3

M. Chapellier , L. Sniadower , G. Dreyfus , H. Alloul , J. Cowen

We have found an unexpectedly large number (2.8 × 1018/cc) of electronic paramagnetic centres in microspheres of fluorocarbon. These centres are peroxy-radicals. We have used them to produce for the first time a dynamic polarization of He3 adsorbed on the surface of the particles. However the origin of the coupling between He3 and fluorine nuclei observed in this system is not yet understood.

Mots clés: adsorbed layers; dynamic nuclear polarisation; helium films; liquid helium 3; paramagnetic resonance of free radicals

Domaines: Articles anciens

M. Chapellier, L. Sniadower, G. Dreyfus, H. Alloul, J. Cowen. EPR studies on fluorocarbon microspheres. Dynamic polarization of fluorine nuclei and adsorbed He3. Journal de Physique, 1984, 45 (6), pp.1033-1038. ⟨10.1051/jphys:019840045060103300⟩. ⟨jpa-00209833⟩