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Updated: Jan 26, 2026
Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
Spectroscopic Determination of an Anion-π Bond Strength
Cate S Anstöter1, Joshua P Rogers1, Jan R R Verlet1
1Department of Chemistry , Durham University , Durham DH1 3LE , United Kingdom.
Abstract:
The anion-π bond has emerged as an important nonvalence interaction in supramolecular and biological structure. Although recognized as a strong noncovalent interaction, driven by electrostatic charge-quadrupole moment and correlation interactions, benchmark experimental and computational studies on the intrinsic anion-π bond strength are scarce. Here, we present a gas-phase photoelectron spectroscopic study on the archetypical iodide-hexafluorobenzene anion-π bonded complex. In combination with high-level electronic structure calculations, the anion-π bond strength is found to be 0.53 eV (51 kJ mol-1). The interaction arises for a large part from correlation forces (∼40%), with electrostatic quadrupole-anion and polarization making up most of the remainder.
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