Anomalous property of Ag(BO2)2 hyperhalogen: does spin-orbit coupling matter?

Area of Science:

• Inorganic Chemistry
• Theoretical Chemistry
• Physical Chemistry

Background:

• Hyperhalogens are a novel class of highly electronegative species.
• These species consist of metals and superhalogens.
• Coinage metals like copper, silver, and gold are key components.

Purpose of the Study:

• To investigate coinage-metal-containing hyperhalogen anions: Cu(BO(2))(2)(-), Ag(BO(2))(2)(-), and Au(BO(2))(2)(-).
• To understand the electronic structure and properties of these hyperhalogens.
• To explore the role of spin-orbit coupling in gold hyperhalogens.

Main Methods:

• High-level ab initio theoretical calculations.
• Photoelectron spectroscopy experiments.
• Analysis of vertical electron detachment energies (VDE).

Main Results:

• Ag(BO(2))(2)(-) exhibits an anomalously high VDE compared to its copper and gold counterparts.
• High-level calculations quantitatively agree with experimental VDE measurements.
• Spin-orbit coupling (SOC) significantly lowers the VDE of Au(BO(2))(2)(-) by approximately 0.5 eV.

Conclusions:

• SOC plays a crucial role in the electronic structure of gold hyperhalogens.
• This study establishes a new framework for relativistic electronic structure calculations of ionic complexes.
• The findings are particularly relevant for understanding one-electron-removal processes in Au(I)L(2) complexes.