Total energy differences between SiC polytypes revisited

The total energy differences between various SiC polytypes (3C, 6H, 4H, 2H, 15R, and 9R) were calculated using the full-potential linear muffin-tin orbital method using the Perdew-Wang generalized gradient approximation [I. P. Perdew, in Electronic Structure of Solids ’91, edited by P. Ziesche and H. Eschrich (Akademie-Verlag, Berlin, 1991), p. 11] to the exchange-correlation functional in the density-functional method. Numerical convergence versus k-point sampling and basis-set completeness are demonstrated to be better than 0.5 meV/atom. The parameters of several generalized anisotropic next-nearest-neighbor Ising models are extracted and their significance and consequences for epitaxial growth are discussed.