MacLaurin expansions of electron momentum densities for 78 diatomic molecules: a numerical Hartree–Fock study

Values of the leading coefficients of the MacLaurin expansion of the electron momentum density Π(p→) are calculated by a fully numerical Hartree–Fock method for 78 diatomic molecules. Large basis set errors are found in previous computations of these quantities using self-consistent-field wave functions often considered to be of near-Hartree–Fock quality. The numerical Hartree–Fock values should be valuable in the development and calibration of basis sets for the calculation of electron momentum densities.