mShort-range nonclassical electron-electron interaction is described by a density functional in a scheme that allows multideterminant wave functions. The parameter that determines the coupling with the configuration-interaction-type calculations can be chosen in a controlled manner. Results are presented for the He and the Be series using a Yukawa-type interaction. 0 1995 John Wiley & Sons, Inc.

No abstract

No abstract

The results of large-scale relativistic ab initio pseudopotential calculations for the potential curve of the 1 Σ g + (0 g + ) ground state of the mercury dimer Hg 2 are reported. Various methods to account for electron correlation effects have been applied in the ΛΣ coupling scheme, and spin-orbit contributions were derived from calculations in the intermediate coupling scheme. The importance of correlating the 5s,5p core orbitals in addition to the 5d core and 6s valence orbitals and of spin-orbit corrections is demonstrated. At the highest level of approximation the calculated spectroscopic constants (R e ) 3.73 Å, D e ) 0.047 eV, ω e ) 19 cm -1 ) are in excellent agreement with the experimental results (R e ) 3.63 ( 0.04 Å, D e ) 0.043 ( 0.003 eV, ω e ) 18.5 ( 0.5 cm -1 ).

No abstract