Electronic thermal property of graphite

The interlayer atomic interactions determine the low-lying band structure of graphite and thus the electronic specific heat. Simple hexagonal graphite presents the greatest specific heat and exhibits a linear temperature-dependence due to the nearly constant density of states. Bernal graphite deviates from the linear T-dependence as temperature is above 100 K. Rhombohedral graphite shows the linear dependence only in the low temperature range, and is revealed to have the lowest specific heat. In addition, monolayer graphene has a T-square dependence. These significant differences in thermal property originate from the stacking symmetry.