Nonrelativistic energy of the Li ground state

Abstract

Configuration-interaction calculations with energy-optimized basis sets and an empirical estimate of all sources of truncation-energy errors are used to evaluate the nonrelativistic electronic energy of the Li ground state. Our result ${\mathit{E}}_{\mathrm{nr}}$=-7.478 062 4(7) a.u. (Li) is 3 μhartree below an upper bound recently obtained by King using Hylleraas-type calculations, and 11 μhartree above an old estimate based on experimental data supplemented by relativistic, radiative, and mass-polarization corrections, thus suggesting a reassessment of several related issues.