Relativistic equation-of-motion coupled-cluster-theory analysis of blackbody radiation shift in the clock transition of Zn i

We employ the equation-of-motion coupled-cluster (EOM-CC) method in the four-component relativistic theory framework to understand the roles of electron correlation effects in the ab initio estimations of electric dipole polarizabilities (α) of the states engaged in the clock transition (¹S₀→³P₀) of the zinc atom. The roles of basis size, inclusion of higher-level excitations, and higher-order relativistic effects in the evaluation of both excitation energies of a few low-lying excited states and α are analyzed systematically. Our EOM-CC values are compared with the earlier reported theoretical and experimental results. This demonstrates the capability of the EOM-CC method to ascertain the preciseness of the blackbody radiation shift in a clock transition, which holds paramount importance for optical clock-based experiments.