An ab initio relativistic coupled-cluster theory of dipole and quadrupole polarizabilities: Applications to a few alkali atoms and alkaline earth ions

We present a new approach based on the relativistic coupled-cluster theory to calculate the first order wave functions due to one-electron perturbation of any rank. Using this method, we calculate the static dipole and quadrupole polarizabilities in some alkali atoms and alkaline earth-metal ions. This is a stringent test of the proposed method as the calculations involve operators of different parities and ranks considering the interplay of both relativistic and correlation effects. Also, the proposed method has a wide range of applications.

We have proposed a new approach to calculate dipole and quadrupole polarizabilities in the atomic systems using the relativistic coupled-cluster theory. We have employed this new method in a few systems to demonstrate how the method works and details of the working procedure are given briefly. Various contributions arising through the new approach are discussed diagrammatically using their counter lower order many-body perturbation theory.