The N1s ESCA Spectrum of Protonated 1,8-Bis-(Dimethylamino) Naphthalene (“proton sponge”)

The ESCA spectrum of protonated 1,8-bis-(dimethylamino) naphthalene (“proton sponge”) (I) has been recorded in the region of N1s binding energies. The results indicate that IH⁺ possesses an unsymmetrical N? H…?N hydrogen bridge.