Uncovering Chemical Homology of Superheavy Elements: A Close Look at Astatine

The fascination with superheavy elements (SHE) spans the nuclear physics, astrophysics, and theoretical chemistry communities. Extreme relativistic effects govern these elements' chemistry and challenge the traditional notion of the periodic law. The experimental quest for SHE critically depends on theoretical predictions of these elements' properties, especially chemical homology, which allows for successful prototypical experiments with more readily available lighter homologs of SHE. This work is a comprehensive quantum-chemical investigation into astatine (At) as a non-intuitive homolog of element 113, nihonium (Nh). Combining relativistic coupled-cluster and density functional theory approaches, we model the behavior of At and AtOH in thermochromatographic experiments on a pristine gold surface. Insights into the electronic structure of AtOH and NhOH and accurate estimates of At–gold and AtOH–gold adsorption energies rationalize recent experimental findings and justify the use of At as a chemical homolog of Nh for the successful design of future experiments on Nh detection and chemical characterization.