Structure and dynamics of molten calcium chloride: ab initio simulations

Structure and transport properties of CaCl2-based melts attract attention due to prospective applications in the field of energy storage and transport, including green technologies. Most effort was aimed at mixed binary and ternary compositions, while pure CaCl2 melt was investigated in less detail. In this paper, molten CaCl2 was simulated using the ab initio molecular dynamics approach. Due to the relatively high duration of the simulation run, both static and dynamic properties were obtained. It was found that preferential Ca coordination cases are [CaCl7] and [CaCl6]. Dynamic properties including vibrational density of states and cation-anion lifetimes show that the structure of the melt does not exhibit stable units. Self-diffusion coefficients calculated from mean squared displacements are in a good agreement with available experimental data.