Thermal behaviour and superheating temperature of Kaolinite from molecular dynamics

The aim of the present work is the investigation of the thermodynamics properties of kaolinite by means of molecular dynamics calculations based on the CLAYFF force field. The obtained results give various thermodynamical quantities, not yet estimated for kaolinite, such as the linear thermal expansion coefficient in the three directions, heat capacities Cp and Cv in the temperature range between 100 and 2088 K and enthalpy. We focussed our efforts, in particular, on the calculation of the superheating point, which is estimated at 1572 K. This value was deduced from the variation of the lattice parameters, volume and enthalpy with temperature. In addition, the solid–liquid transformation was also seen from the flattening of the atomic density profiles and radial distribution functions, where the order is lost in the bulk structure.