Electric dipole polarizabilities of alkali metal ions from perturbed   relativistic coupled-cluster theory
  We use the perturbed relativistic coupled-cluster theory to compute the static electric dipole polarizabilities of the singly ionized alkali atoms, namely, Na$^+$, $^+$, Rb$^+$, Cs$^+$ and Fr$^+$. The computations use the Dirac-Coulomb-Breit Hamiltonian with the no-virual-pair approximation and we also estimate the correction to the static electric dipole polarizability arising from the Breit interaction. 
S. Chattopadhyay and B. K. Mani and D. Angom
physics.atom-ph