Relativistic effects in gold chemistry. I. Diatomic gold compounds

TLDR

The study performs nonrelativistic and relativistic Hartree–Fock and configuration interaction calculations to analyze relativistic and correlation effects in various diatomic gold compounds. These calculations employ HF and CI methods to probe how relativistic effects influence gold–ligand bonding. Relativistic effects reverse property trends down group 11, causing ligand‑dependent bond destabilization (e.g., AuF) or stabilization (AuLi), with bond contractions between 1.09 and 0.16 Å, and the study predicts unmeasured spectroscopic properties such as bond lengths, dissociation energies, force constants, and dipole moments.

Abstract

Nonrelativistic and relativistic Hartree–Fock (HF) and configuration interaction (CI) calculations have been performed in order to analyze the relativistic and correlation effects in various diatomic gold compounds. It is found that relativistic effects reverse the trend in most molecular properties down the group (11). The consequences for gold chemistry are described. Relativistic bond stabilizations or destabilizations are dependent on the electronegativity of the ligand, showing the largest bond destabilization for AuF (86 kJ/mol at the CI level) and the largest stabilization for AuLi (−174 kJ/mol). Relativistic bond contractions lie between 1.09 (AuH+) and 0.16 Å (AuF). Relativistic effects of various other properties are discussed. A number of as yet unmeasured spectroscopic properties, such as bondlengths (re), dissociation energies (De), force constants (ke), and dipole moments (μe), are predicted.