The electronic and structural properties of graphite have been determined in the local-density approximation with our precise total-energy full-potential linearized augmented-plane-wave method. We confirm the presence of a low-lying unoccupied ${\Gamma }_1^{+}$ interlayer state, which is of importance for intercalation compounds. A careful study of the convergence of the numerical results was needed in order to obtain reliable data for the total energy. Our values of the lattice parameters and their pressure dependence are in good agreement with experiment. The values of the elastic constants $C_{11}$+$C_{12}$ and $C_{33}$ agree with their experimental counterparts. The experimental value of $C_{13}$ differs from our result, and is also inconsistent with the experimental results for the lattice parameters under pressure; new experiments are suggested to resolve this inconsistency.

• Received 31 October 1986

DOI:https://doi.org/10.1103/PhysRevB.35.8207