The thermal conductivity decomposition of calcite calculated by molecular dynamics simulation

Calcite based materials are being used in a range of new energy technologies for power generation and energy storage; in addition to their traditional use in manufacturing, agri-food industry and medicine. The optimum design of these new energy technology platforms requires an in-depth knowledge of the thermo-physical properties of calcite. In this study, the lattice thermal conductivity of calcite (CaCO₃) is investigated in detail over a wide temperature range. Calculations are performed within the framework of equilibrium molecular dynamics simulations in conjunction with the Green-Kubo formalism. To describe the interatomic interactions, the potential parameters of the shell model potentials for calcite developed by Pavese et al. are used. Within the framework of this model we calculate the heat current autocorrelation function over the temperature range of 200–800 K for averages over the NPT, NVT and NVE ensembles in the a- and c- directions. It is revealed that the lattice thermal conductivity can be decomposed into three contributions due to the optical, acoustic short- and long-range phonon modes. Finally, results from this study can be compared with previous related dielectric materials and experimental studies, with good agreement.