C3N3 ring atoms in N and C ssNMR spectra of PTI-IF are shifted slightly to higher ppm values compared to the PTI-LiBr. This finding indicates that nuclei are de-shielded by the removal of ions; an effect that stems from a reduction of electron density at the carbon and nitrogen nuclei. We corroborate this experimental observation by Bader partial charge analysis based on DFT results (Figure ). In PTI-LiBr we observe an increased electron density from the interaction of bromide orbitals with the CN-orbitals.