Salts derived from the interaction of guanine or cytosine acid derivatives with hexadecylamine exhibited smectic liquid crystalline character. This behavior was attributed to a two-level organization process, i.e., to the segregation of lipophilic from hydrophilic moieties due to the formation of the n-alkylammonium salts and to the self-dimerization of these salts through molecular recognition. Furthermore, mixing of the complementary salts in 1:1 molar ratio led, at elevated temperatures, to the formation of their heterodimer which also exhibited a smectic liquid crystalline phase.