First-order relativistic corrections to response properties: the hyperpolarizability of the Ne atom

The computation of first-order relativistic corrections to electrical response properties has been implemented into the Dalton program at the level of closed-shell coupled-cluster theory, within the framework of the direct perturbation theory (DPT) of relativistic effects. Calculations of the first-order relativistic DPT corrections to the static and frequency-dependent dipole polarizability (alpha) and second dipole hyperpolarizability (gamma) of the Ne atom illustrate possible applications of the new code.