Unveiling Multilayered Metal Cation−π(Arene) Interactions in a Structurally Engineered Silver(III)-Corrole: Insights from Terahertz Spectroscopy

Metal cation−π interactions, involving electrostatic forces between a metal cation and an aromatic π-electron cloud, play a critical role in molecular recognition, catalysis, and the design of functional materials. In this work, we combined synthetic, terahertz (THz) spectroscopic, and structural/computational study to provide valuable insights into the nature and characterization of these interactions in a tailor-made silver corrole complex, where a 2-(3-(2-formylphenoxy)propoxy)phenyl group creates an appropriate electronic environment around the silver(III) center for possible metal cation−π(arene) interactions. The observed close Ag···C distances in the crystal structure support the metal cation−π interaction. Critically, THz spectroscopy provided direct experimental evidence for the presence and nature of these interactions, a finding further corroborated by computational studies. To our knowledge, this represents the first application of frequency-domain THz spectroscopy in demonstrating multilayered metal cation−π interactions within such systems. The observed η6-coordination of the silver ion to the aromatic ring highlights its importance in structuring and stabilizing the metal–ligand complex. These findings offer valuable information for designing future molecular systems where metal cation−π interactions are central to structure and stability, with implications for catalysis and material science.