Fig. 13. The electronic spin density distribution for the lowest energy orientation between nitrobenzene and TEMPO where ortho and meta C–H moieties complex with the TEMPO N–O group. Dashed lines are given as guides for intermolecular distances, which are 2.45 Å for O···H (of ortho C–H) and 2.53 Å for N···H (of para C–H).