Dependence of Specific Heat on the Chirality and Diameter of Single-Walled Carbon Nanotubes

Based on special functions, the specific heats of SWCNT types (zigzag and armchair tubes) were theoretically simulated with increasing n (indices of chirality) and consequently d (diameter). It was found that specific heat of carbon nanotubes increased as the chirality and diameter increased, which might be due to transverse acoustic (TA) phonon modes. The results showed that contribution to the specific heat from TA modes varied linearly with temperature and became saturated after a definite temperature. All the studies and results indicated critical role of transversal phonon modes in increasing specific heat with respect to n and d.