A Relativistic Equation-of-motion Coupled-Cluster Investigation of the Trends of Single and Double Ionization Potentials in the He and Be Isoelectronic Systems

Abstract

We employ four-component spinor relativistic equation-of-motion coupled-cluster (EOMCC) method within the single- and double- excitation approximation to calculate the single ionization potentials (IPs) and double ionization potentials (DIPs) of the He and Be isoelectronic sequences up to Ne. The obtained results are compared with the available results from the National Institute of Standards and Technology (NIST) database to test the performance of the EOMCC method. We also present intermediate results at different level of approximations in the EOMCC framework to gain insight of the effect of electron correlation. Furthermore, we investigate the dependence of the IPs and DIPs of these ions on the ionic charge and observe that these follow parabolic trends. Comparison between the trends of IPs and DIPs in both the classes of considered systems are categorically demonstrated.

8 pages, 3 figures

References in corpus (3)

• Relativistic equation-of-motion coupled-cluster method for the ionization problem: Application to molecules
• Relativistic equation-of-motion coupled-cluster method for the double ionization potentials of the closed-shell atoms
• Implementation and Application of the Relativistic Equation of Motion Coupled-cluster Method for the Excited States of Closed-shell Atomic Systems

Cited by in corpus (2)

• Relativistic EOM-CCSD for core-excited and core-ionized state energies based on the 4-component Dirac-Coulomb(-Gaunt) Hamiltonian
• Relativistic double-ionization equation-of-motion coupled-cluster method: Application to low-lying doubly ionized states