Investigation of the thermal conductivity of tetrabenzo[8]circulene (TB8C) by molecular dynamics simulation

Abstract

ABSTRACT In this work we investigated the thermal conductivity of tetrabenzo[8]circulene (TB8C) through the Equilibrium Molecular Dynamics (EMD) simulations. Through this investigation we propose an estimated value for the thermal conductivity of TB8C not yet reported in the literature. The TB8C thermal conductivity was simulated for different temperatures. We compared the average thermal conductivity value, (216 ± 2) W m−1 K−1 with the simulated thermal conductivity of graphene, carbon nanotube and C80H30 molecule, reported in the literature. This comparison suggests that the size and structure containing defects of TB8C, in relation to the intrinsic graphene plane hexagonal structure model, are responsible for its good thermal conductivity. To clarify the mechanism of the thermal behaviour of TB8C, we calculated the Phonon Density of States (PHDOS) and compared with C80H30 and graphene. When compared to graphene, a higher phonon density of state is observed for the TB8C in the frequency range from 0 to 10 THz, which may be an explanation for the high thermal conductivity of the TB8C. By calculating the group velocity, we proposed the hypothesis that the lifetime of phonons, for TB8C, should be greater than that of graphene and proposed that thermal transport should occur, predominantly, in ballistic form.