High-Accuracy Calculations for Heavy and Super-Heavy Elements

TLDR: In this article, the relativistic coupled cluster method was used to calculate energy levels of heavy and super-heavy (Z>100) elements by starting from the four-component solutions of the Dirac-Fock or Dirac Fock-Breit equations, and correlates them by the coupled-cluster approach.

Abstract: Energy levels of heavy and super-heavy (Z>100) elements are calculated by the relativistic coupled cluster method. The method starts from the four-component solutions of the Dirac-Fock or Dirac-Fock-Breit equations, and correlates them by the coupled-cluster approach. Simultaneous inclusion of relativistic terms in the Hamiltonian (to order α 2 , where α is the fine-structure constant) and correlation effects (all products and powers of single and double virtual excitations) is achieved. The Fock-space coupled-cluster method yields directly transition energies (ionization potentials, excitation energies, electron affinities). Results are in good agreement (usually better than 0.1 eV) with known experimental values. Properties of superheavy atoms which are not known experimentally can be predicted. Examples include the nature of the ground states of elements 104 and 111. Molecular applications are also presented.