Standardized basis sets for high-level-correlated relativistic calculations of atomic and molecular electric properties in the spin-averaged Douglas-Kroll approximation

Abstract

The technique previously developed for the generation of the so-called first-order polarized basis sets for accurate non-relativistic calculations of molecular electric properties is used to obtain similar basis sets suitable for calculations in the Douglas-Kroll no-pair approximation. The corresponding (relativistic) basis sets are constructed for atoms of groups Ia and IIa of the Periodic Table and tested in calculations of atomic and ionic polarizabilities. Also the first ionization potential of the group Ia and the first and second ionization potential of the group IIa metals have been evaluated to provide additional qualification of the generated basis sets. The present results are compared with earlier non-relativistic and quasirelativistic data and the role of the relativistic effect is discussed.