Extended Douglas-Kroll transformations applied to the relativistic many-electron Hamiltonian
Abstract
A new generalized Douglas-Kroll (DK) approach is proposed for the relativistic many-electron Hamiltonian including the electron-electron interaction. In order to consider the higher-order DK transformation to the two-electron interaction, the present approach adopts the effective one-electron potential in the Dirac-Hartree-Fock/Dirac-Kohn-Sham operator as an expansion parameter in the DK transformation. Its numerical performance is tested for the atomic Hg and molecular HAt and At2 systems. The third-order DK transformation to both one-electron and two-electron Hamiltonians, which is the highest level of theory treated in this study, gives excellent agreement with the four-component relativistic approach. The first-order DK correction to the two-electron interaction is shown to be satisfactory for both atomic and molecular systems.
- Publication:
-
Journal of Chemical Physics
- Pub Date:
- August 2003
- DOI:
- 10.1063/1.1594173
- Bibcode:
- 2003JChPh.119.4105N
- Keywords:
-
- 31.30.Jv;
- 31.15.-p;
- Relativistic and quantum electrodynamic effects in atoms and molecules;
- Calculations and mathematical techniques in atomic and molecular physics