A highly effective halide anion sponge containing tellurium σ-hole

Abstract

Chalcogen bonding has attracted lots of attention recently due to possessing good tunability and significant directionality. A novel and highly effective anion sponge ligand (L) capable of capturing halide anions was designed using chalcogen bond. Quantum chemistry calculations show the sponge can bind the halide anions by one or two chalcogen bonds through several binding modes. The binding free energies range from −40.0 to −77.0 kcal mol−1 in gas phase, from −11.0 to −35.0 kcal mol−1 in aqueous solution, with a common trend of F->Cl-> Br->I-. L shows extremely high selectivity for F- with respect to other halide anions. Electronic structure analyses further reveal the chalcogen bonding between halide anions and Te σ-hole may be regarded as an ionic bond.