Anion-dependent ion-pairing assemblies of triazatriangulenium cation that interferes with stacking structures.

Ion pairs of -(2,6-dimethylphenyl)-substituted triazatriangulenium (TATA) cation with various counteranions were synthesized to investigate the interactions for the bulky cation. Single-crystal X-ray analysis of the TATA ion pairs revealed solid-state ion-pairing assemblies without stacking at the cationic π-planes. The TATA cation showed counteranion-dependent assembly structures, with smaller counteranions located at the top of TATA and bulkier counteranions displaced from the TATA plane to interact with the surrounding TATA.