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.