π‐Electronic communication through mono and multinuclear gold(I) complexes

We have theoretically studied gold(I) complexes of the type L 1 ‐Au I ‐L 2 and HCN‐[Au I ‐CN] n ( n = 1–8) using relativistic density functional theory at ZORA‐BP86/TZ2P. Our purpose, besides determining structure and stability, is to analyze the bonding in our model systems in the conceptual framework of Kohn–Sham molecular orbital theory in combination with a quantitative bond energy decomposition scheme and analysis of the charge distribution. We focus on the π‐bonding interaction for a given ligand‐gold coordination bond and how this is affected by the presence of the other ligand. We find pronounced π‐electronic communication through the gold(I) valence shell in complexes that involve a π‐donor as well as a π‐acceptor ligand. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009