Dynamic nuclear polarization via confined electrons in bulk solids

Abstract

Nuclear polarization dynamics arising from saturation of the EPR of an electron-rich component of a composite polymer material are reported. The unpaired electrons are confined to islands of polyacetylene embedded in a matrix of polyethylene. The interaction among the three kinds of spin in the sample (unpaired electrons, 13C, and 1H, their natural abundance, and the fact that the electrons are confined to small regions of the sample lead to a rich variety of spin dynamics constituting a solid-state analog of the "three-spin" effect discovered in solution DNP studies several years ago. © 1989.