Structure and infrared spectrum of the Ag(+)-phenol ionic complex

Area of Science:

• Physical Chemistry
• Spectroscopy
• Computational Chemistry

Background:

• Understanding metal-ligand interactions is crucial in chemistry.
• The Ag(+)-phenol complex is a model system for studying metal-aromatic interactions.

Purpose of the Study:

• To determine the preferred binding site of the Ag(+) ion in the phenol cationic complex.
• To characterize the structure and infrared (IR) spectrum of the Ag(+)-phenol complex in the gas phase.

Main Methods:

• Infrared (IR) multiple photon dissociation (IRMPD) spectroscopy.
• Gas-phase photodissociation spectroscopy.
• Quantum chemical calculations (MP2 and B3LYP levels with aug-cc-pVTZ basis set).
• Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry with electrospray ionization.

Main Results:

• The IRMPD spectrum analysis indicates a π complex formation.
• The Ag(+) ion binds to the aromatic ring, specifically at the para position relative to the OH group.
• Calculations suggest η(1) (B3LYP) or η(2) (MP2) binding modes.
• σ complex formation (Ag(+) bonding to the hydroxyl group) is less favorable.
• Partial charge transfer occurs upon π complex formation.

Conclusions:

• The Ag(+) ion preferentially binds to the aromatic ring of phenol via a π interaction.
• Spectroscopic and computational data support the π complex structure.
• The study provides insights into the electronic interactions between silver ions and aromatic systems.