The measured isotropic shifts are well outside the typical region of 1 H/ 2 H shifts (0 12 ppm). This indicates the presence of the hyperfine interaction between the nuclei and unpaired electrons, which can lead to large isotropic shifts and shift anisotropies. In the polaron state the source of unpaired electrons would be the electron polaron, while for the bandstate the conduction electrons. In both cases the main contribution to shift would arise from the Fermi contact (FC) term. In metals the NMR shift is called the Knight shift K with a Fermi contact part K FC given by: