Relativistic coupled-cluster calculation of the electric dipole polarizability and correlation energy of Cn, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow><mml:mi>Nh</mml:mi></mml:mrow><mml:mo>+</mml:mo></mml:msup></mml:math>, and Og: Correlation effects from lighter to superheavy elements
Ravi Kumar, S. Chattopadhyay, D. Angom, B. K. Mani
Abstract
We employ a relativistic coupled-cluster theory to compute the ground-state electric dipole polarizability $\ensuremath{\alpha}$ and the electron correlation energy of the superheavy elements Cn, ${\mathrm{Nh}}^{+}$, and Og. To assess the electron correlation trends with $Z$, we also compute the correlation energies of the three lighter homologs for each of the elements. In the computations, we use the Dirac-Coulomb-Breit Hamiltonian and incorporate the quantum electrodynamical corrections from the Uehling potential and the self-energy. The effects of triple excitations are considered perturbatively in the theory. Our recommended values of $\ensuremath{\alpha}$ are in good agreement with previous theoretical results. As expected, the dominant contribution is from the valence electrons. Except for Cn and Og, the contribution from the Breit interaction decreases with $Z$. For the vacuum polarization and self-energy corrections, the contributions increase with $Z$. To understand the correlation energy trends better, we also compute the correlation energy with the relativistic many-body perturbation theory.