Self-organization at the interface and in aqueous solution of a cationic gemini surfactant from the dioctyl ester of cystine

► Dioctyl ester of cystine hydrochloride (DOEC) forms stable viscoelastic films at the air-water interface. ► CMC is about one order lower than the equivalent anionic surfactant from cystine. ► The molecular cross-sectional area at the interface was measured as 0.70 ± 0.01 nm2 molecule−1. ► DOEC exhibits a tilted conformation at the interface, and the large packing parameter P of 0.58 suggests the formation of elongated micelles. ► DOEC favors one-dimensional growth to form fibril like structures.