Ion association and solvation in solutions of Mg2Â +, Ca2Â +, Sr2Â +, Ba2Â + and Ni2Â + perchlorates in acetonitrile: Conductometric study

► Conductance of Mg2 +, Ca2 +, Sr2 +, Ba2 + and Ni2 + perchlorates in acetonitrile. ► The primary association constant and limiting equivalent conductivities are derived. ► Strong solvation of Mg2 + and Ni2 + prevents formation of contact ion pairs. ► SrClO4+ and BaClO4+ exist in acetonitrile mainly as contact ion pairs. ► The modified theory of dielectric friction describes dynamics of solvated ion.