Correlation trends in the ground-state static electric dipole polarizabilities of closed-shell atoms and ions

Abstract

We employ the closed-shell perturbed relativistic coupled-cluster (RCC) theory developed by us earlier [Phys. Rev. A 77, 062516 (2008)] to evaluate the ground-state static electric dipole polarizabilities ($\ensuremath{\alpha}$s) of several atomic systems. In this work, we have incorporated a class of higher-order many-body effects in our calculations that had not been taken into account in the above paper. We highlight their importance in improving the accuracies of $\ensuremath{\alpha}$s. We also calculate the ground state $\ensuremath{\alpha}$s of the inert gas atoms and several isoelectronic singly and doubly charged ions in order to make a comparative study of the trends of the correlation effects. Furthermore, we have developed a method to construct intermediate diagrams that are required for the computations of the unperturbed single and doubl coupled-cluster amplitudes. Our RCC results are compared with those of many-body perturbation theory at different orders to demonstrate the importance of higher-order correlation effects for the accurate determination of ($\ensuremath{\alpha}$s) of the systems that we have considered.