Abstract
An analysis is made of the exact treatment for the orthogonalization hole potential, denoted by nu OPW*, in Harrison's first principle pseudopotential theory (1966, 1969). A corrected form of Harrison's expression for the approximation of nu OPW* is given and its effect on the calculation of phonon spectra for lithium, sodium and zinc are discussed. To demonstrate the effect of using the 'exact' formulation for the orthogonalization hole potential, the nu OPW* and an exact orthogonalization hole density are used in the calculation of a nonlocal pseudopotential and phonon dispersion curves for zinc.