A conductance study of the interaction between TlC ion and 18-crown-6 (18C6), dicyclohexano-18-crown-6 (DC18C6),benzo-18-crown-6 (B18C6), diaza-18-crown-6 (DA18C6), dibenzyldiaza-18-crown-6 (DBzDA18C6) and hexaaza-18-crown-6 (HA18C6) in dimethylformamide-acetonitrile mixtures was carried out at various temperatures. The formation constants of the resulting 1 : 1 complexes were determined from the molar conductance-mole ratio data and found to vary in the order HA18C6 > DA18C6 > DBzDA18C6 > 18C6 > DC18C6 > B18C6. The enthalpy and entropy of the complexation reactions were determined from the temperature dependence of the formation constants
