THEORETICAL INSIGHTS INTO CHALCOGEN BONDING ASSISTED ANION RECOGNITION

This work emphasizes the potential of (benzo)chalcogenadiazole in recognizing anions via chalcogen bonding as a key interaction. We employed various theoretical tools to analyse the binding affinity and selectivity of substituted (benzo)thiadiazole for fluoride. The molecular electrostatic potential surface provided qualitative insights into the influence of substituents on electronic properties and the 𝜎 hole of the sulfur atom in directing the interaction strength with the anionic counterpart. Quantitative evaluations using symmetry-adapted perturbation theory, natural bond orbital analysis and topological descriptors at bond critical points confirmed the interaction mechanisms. Notably, the study revealed that the S···F- bond strength was moderately enhanced for bis(trifluoromethyl)thiadiazole compared to tetrafluorobenzothiadiazole. Finally, the significant S···F- bond was found to exhibit a partial covalent character, which has important implications for the design of novel chalcogenadiazole-derived anion receptors and sensors, contributing to the advancement of anion recognition.