Аннотация:The magnitudes of the enthalpies of complexation of CaCl2 with benzo-12-crown-4 (I) and benzo-15-crown-5 were smaller than those for complexation of CaCl2 with 12-crown-4 and 15-crown-5. CaCl2 and Ca(SCN)2 formed 1:1 and 1:2 complexes with I. The anion of the Ca salt had an appreciable effect on the enthalpy of complexation. No complexation could be established with Ca(NO3)2.