Molecular dynamics simulations have been carried out on molten (Nd 1/3 , K)Cl at 1065 and 1073 K and (Nd 1/3 , Na)Cl at 1124 K for various compositions. The calculated self-exchange velocity (v ), self-diffusion coefficient (D), electrical conductivity (k) and enthalpy of mixing ( ΔH mix ) were compared with the corresponding experimental values. The calculated results revealed that v and D of potassium decrease with increasing anmount of neodymium, as expected from the experimental internal mobility (6). The decrease of b K , v K , and D K are attributed to the tranquilization effect by Nd 3+ which strongly interacts with Cl - as well as Dy 3+ . On the contrary, b Nd , V Nd, and D Nd increase with increasing concentration of Nd 3+ . This might be ascribed to the stronger association of Nd 3+ with Cl - due to the enhanced charge asymmetry of the two cations neighboring Cl - . In addition, the sequences of the calculated v's, D's and k ’s for the various compositions were consistent with those of the known experimental results. The experimental enthalpy of mixing with its negative dependence on the cation size was qualitatively reproduced.