Toward a unified single-parameter extrapolation scheme for the correlation energy: Systems formed by atoms of hydrogen through neon.

A simple scheme is suggested to extrapolate the valence electron correlation to the one-electron complete-basis-set limit in species formed by atoms of hydrogen through neon. The performance of the novel scheme is benchmarked for the correlation energy with a data set of 106 systems and, for the polarizability, with 8 molecules. For the former, the results are excellent, most often better than when extrapolated with the best available two-parameter protocols. For the polarizability, they show an enhancement relative to the raw ab initio values, and good agreement with the experimental ones. [ABSTRACT FROM AUTHOR]