Investigation of thermal properties of crystalline alpha quartz by employing different interatomic potentials: A molecular dynamic study

Abstract

In the present work, the thermal properties of crystalline α-quartz, including thermal conductivity (TC) and thermal expansion coefficient (TEC), are studied using the non-equilibrium molecular dynamics (NEMD) simulation method. Since there is a dependence on interatomic potentials in simulation results, the thermal conductivity and thermal expansion coefficient of crystalline α- quartz is computed using various force fields in a temperature range from 200 K to 1000 K compare which concurs better with experimental findings. Arising from the present molecular dynamic simulation by different force fields such as Tersoff, Vashishta, Stillinger-Weber, Meam, BKS, ReaxFF, and Morse, the thermal conductivities that were carried out using the ReaxFF and BKS are more accurate. It is also founded that predicted thermal conductivity at higher temperatures shows a better agreement with experimental values. In terms of TEC, Tersoff and SW corroborate the experimental remarks and give a smaller magnitude of TEC in z direction. On the other hand, in contradiction with the other force fields, Meam potential presents no significant TEC variation with temperature alteration. © 2021 Elsevier B.V.