Estimates of the Spontaneous Polarization and Permittivities of AlN, GaN, InN, and SiC Crystals

The values of spontaneous polarization and permittivities of aluminum, gallium, and indium nitrides, as well as silicon carbide, with a wurtzite structure are calculated within the Harrison bond-orbital model. The only fitting parameter gamma, which characterizes corrections for a local field, is determined from the fit of the calculated high-frequency permittivity epsilon(infinity) to the experimental data for compounds with a sphalerite structure. The results obtained are in satisfactory agreement with the available experimental data and calculations performed by other authors.