Accurate Gaussian basis sets for second-row atoms and ions generated with the improved generator coordinate Hartree–Fock method

Abstract

The improved generator coordinate Hartree–Fock (IGCHF) method is used to generate accurate Gaussian basis sets for the second-row neutral atoms, singly charged cations from Na + through Ar +, and stable singly charged anions from Na − through Cl −. For all second-row atoms and ions studied, the ground-state energies obtained with the triply-optimized Gaussian basis sets (generated with the IGCHF method) are always better than those obtained with the original generator coordinate Hartree–Fock method, and do not differ from the corresponding numerical Hartree–Fock results by more than 0.8 millihartree.