Density-functional calculations of semiconductor properties using a semiempirical exchange-correlation functional

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Abstract
We investigate the applicability of the semiempirical Hamprecht-Cohen-Tozer-Handy (HCTH) exchange-correlation functional, which was optimized by fitting to molecular systems, to the calculation of semiconductor lattice constants, bulk moduli, cohesive energies, and electronic band gaps. Plane-wave pseudopotential calculations are performed on a series of diamond and zinc-blende semiconductors and HCTH values are compared with the local density approximation (LDA) and the Perdew-Wang generalized gradient approximation (PW91). The HCTH functional provides a reasonably accurate description for carbon-diamond, although as the periodic table is descended the results become progressively less accurate. This reflects the predominance of low-atomic-number atoms in the fitting data used to determine the HCTH functional. HCTH electronic band gaps are generally larger than PW91 and LDA, but are still significantly below experiment.