We use perturbed relativistic coupled-cluster (PRCC) theory to compute the electric dipole polarizabilities α of Zn, Cd and Hg. The computations are done using the Dirac-Coulomb-Breit Hamiltonian with Uehling potential to incorporate vacuum polarization corrections. The triple excitations are included perturbatively in the PRCC theory, and in the unperturbed sector, it is included non-perturbatively. Our results of α, for all the three elements, are in excellent agreement with the experimental data. The other highlight of the results is the orbital energy corrections from Breit interactions. In the literature we could only get the data of Hg [1] and are near perfect match with our results. We also present the linearized equations of the cluster amplitudes, including the triple excitations, with the angular factors.PACS numbers: 31.15.bw,31.15.ap,31.15.A-,31.15.ve

The perturbed relativistic coupled-cluster (PRCC) theory is applied to calculate the electric dipole polarizabilities of alkaline Earth metal atoms. The Dirac-Coulomb-Breit atomic Hamiltonian is used and we include the triple excitations in the relativistic coupled-cluster (RCC) theory. The theoretical issues related to the triple excitation cluster operators are described in detail and we also provide details on the computational implementation. The PRCC theory results are in good agreement with the experimental and previous theoretical results. We, then, highlight the importance of considering the Breit interaction for alkaline Earth metal atoms.PACS numbers: 31.15.bw,31.15.ap,31.15.A-,31.15.ve

We use perturbed relativistic coupled-cluster (PRCC) theory to calculate the electric dipole polarizability of noble gas atoms Ar, Kr, Xe and Rn. We also provide a detailed description of the nonlinear terms in the PRCC theory and consider the Dirac-Coulomb-Breit atomic Hamiltonian for the calculations. We find that the largest contribution from Breit interaction to the electric dipole polarizability is 0.1%, in the case of Rn. As we go from Ar to Rn, based on the pattern in the random phase approximation effects, the contraction of the outermost p 1/2 due to relativistic corrections is discernible without any ambiguity. PACS numbers: 31.15.bw,31.15.ap,31.15.A-,31.15.ve arXiv:1210.5471v1 [physics.atom-ph]

We develop a method based on the relativistic coupled-cluster theory to incorporate a perturbative interaction to the no-pair Dirac-Coulomb atomic Hamiltonian. The method is general and suitable to incorporate any perturbation Hamiltonian in a many-electron atom or ion. Using this perturbed relativistic coupled-cluster (PRCC) theory, we calculate the electric-dipole polarizability α of neon. The linearized PRCC results are in very good agreement with the experimental value. However, the results of the nonlinear PRCC theory show larger uncertainty, but they are consistent with the observations from earlier works.

We use the perturbed relativistic coupled-cluster theory to compute the static electric dipole polarizabilities of the singly ionized alkali atoms, namely, Na + , K + , 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.PACS numbers: 31.15.bw,31.15.ap,31.15.A-,31.15.ve