Halogen-like Behavior of Gold: Can Gold Form Pseudo-Halogen Bonds?

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Quantum Chemistry

Background:

• Gold shares electronegativity and electronic properties with halogens.
• Halogen bonds (XBs) are crucial non-covalent interactions.
• Superhalogen species formation is a known halogen characteristic.

Purpose of the Study:

• To investigate gold's halogen-like bonding behavior.
• To explore the formation and characteristics of pseudo-halogen bonds (pseudo-XBs) involving gold.
• To compare gold-based pseudo-XBs with conventional halogen bonds.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Systematic comparison of homonuclear and heteronuclear dimers and clusters of halogens and metals (Cu, Ag, Au).
• Analysis using Quantum Theory of Atoms in Molecules (QTAIM) and Energy Decomposition Analysis (EDA).

Main Results:

• Gold forms zigzag configurations in dimers (Au2···Au2, FAu···AuF) analogous to halogens.
• Gold-based pseudo-XBs exhibit greater interaction strength than conventional XBs.
• The nature of gold's pseudo-XBs is similar to XBs, dominated by orbital interactions and electronic correlation.

Conclusions:

• Gold can act as a halogen-like center in specific cluster families.
• Pseudo-XBs involving gold are a significant area for further chemical bonding research.
• These findings offer new perspectives on the chemical behavior of gold.