4-(N aphthalene-2-carboxamido)pyridin1-ium thiocyanate-N-(pyridin-4-y1)naphthalene-2-carboxamide (1/1)

The asymmetric unit of the title compound, C6H13N2O+ NCS--C16H12N2O, contains two N-(pyridin-4-yl)naphthalene2-carboxamide molecules, both are partially protonated in the pyridine moiety, i.e. the H atom attached to the pyridine N atom is partially occupied with an occupancy factor of 0.61 (3) and 0.39 (3), respectively. In the crystal, protonated and neutral N-(pyridin-4-yl)naphthalene-2-carboxamide molecules are linked by N-H center dot center dot center dot N hydrogen bonding; the thiocyanate counter -ion links with both protonated and neutral N-(pyridin-4-yl)naphthalene-2-carboxamide molecules via N-H center dot center dot center dot S and N-H center dot center dot center dot N hydrogen bonding. The dihedral angles between the pyridine ring and naphthalene ring systems are 11.33 (6)degrees and 9.51 (6)degrees, respectively. pi-pi stacking is observed in the crystal structure, the shortest centroid-centroid distance being 3.5929 (8) angstrom. The crystal structure was determined from a nonmerohedral twin {ratio of the twin components = 0.357 (1):0.643 (1) and twin law [100 010 Tom.