Imaging the halogen bond in self-assembled halogenbenzenes on silver
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Updated: Feb 22, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Zhumin Han1, Gregory Czap1, Chi-Lun Chiang1
1Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575, USA.
Abstract:
Halogens are among the most electronegative elements, and the variations in size and polarizability of halogens require different descriptions of the intermolecular bonds they form. Here we use the inelastic tunneling probe (itProbe) to acquire real-space imaging of intermolecular-bonding structures in the two-dimensional self-assembly of halogenbenzene molecules on a metal surface. Direct visualization is obtained for the intermolecular attraction and the "windmill" pattern of bonding among the fully halogenated molecules. Our results provide a hitherto missing understanding of the nature of the halogen bond.
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