One-electron properties of several small molecules using near Hartree–Fock limit basis sets

Selected one-electron properties for eight small molecules (H2O, CO, N2, H2S, NH3, PH3, HCl, and HF) have been computed using extended Gaussian basis sets at the SCF and CI levels. The basis sets and CI methodologies were capable of recovering approximately 86% of the estimated total correlation energy (88% of the valence) and, to the best of our knowledge, yielded the lowest variational energies and closest overall agreement with experimentally determined properties to date. Compared to numerical Hartree–Fock properties the current values are generally within 1%, with the largest deviation being 2.6% for δ at the nucleus. The sensitivity of the computed properties to the basis set composition and type of CI are discussed.