Charge density distribution in the 'proton sponge' compound 1,8-bis(dimethylamino)naphthalene

Research was conducted to examine the charge distribution in an uncomplexed proton sponge compound through low-temperature, high-resolution X-ray and neutron diffraction methods. A small degree of asymmetry of the naphthalene moiety, which was induced by weak, asymmetric intermolecular interactions, was observed. Results demonstrate that protonation affects the atomic charges and structural parameters such as C-C, C-N and C-H bond lengths.