The comparison of theory and experiment for energy levels of strongly bound electrons
provides a critical test of quantum electrodynamics in strong fields. A theoretical evaluation …

Because of the well-understood nature of the electromagnetic interaction, the presence of a
well-defined center of force, and the relative unimportance of nonperturbative effects, the …

The relativistic Fock-space coupled cluster method for the direct calculation of ionization
potentials and excitation energies (including fine structure) is presented and applied to …

The relativistic Fock-space coupled-cluster method was applied to the Yb, Lu, and Lr atoms,
and to several of their ions. A large number of transition energies was calculated for these …

A complete, numerical calculation of the effect of the exchange of two virtual photons
between the electrons in the ground states of heliumlike systems is presented. Feynman …

Complete relativistic and quantum electrodynamics corrections of order α 2 Ry and α 3 Ry
are calculated for the ground state of the beryllium atom and its positive ion. A basis set of …

Explicitly correlated Gaussian functions are applied to extensive variational calculations of
the 1 S ground state of the beryllium atom. The convergence of the energy with respect to …

Ground-and excited-state energies, as well as ionization potentials and electron affinities,
are calculated for all the alkali-metal atoms Li–Fr by the relativistic Fock-space coupled …

A brief review is given of the historical development of the treatment of the correlation
problem in solving the Schrödinger equation in modern quantum theory from the early …

The relativistic coupled-cluster method starts from the Dirac–Coulomb–Breit Hamiltonian in
its low-frequency approximation and includes correlation by Fock-space coupled-cluster …