Halogen bonding (XB) has emerged as an important bonding motif in supramolecules and biological systems. Although regarded as a strong noncovalent interaction, benchmark measurements of the halogen bond energy are scarce. Here, a combined anion photoelectron spectroscopy and density functional theory (DFT) study of XB in solvated Br−anions is reported. The XB strength between the positively‐charged σ‐hole on the Br atom of the bromotrichloromethane (CCl3Br) molecule and the Br−anion was found to be 0.63 eV (14.5 kcal mol−1). In the neutral complexes, Br(CCl3Br)1,2, the attraction between the free Br atom and the negatively charged equatorial belt on the Br atom of CCl3Br, which is a second type of halogen bonding, was estimated to have interaction strengths of 0.15 eV (3.5 kcal mol−1) and 0.12 eV (2.8 kcal mol−1).
Halogen bonding (XB) has emerged as an important bonding motif in supramolecules and biological systems. Although regarded as a strong noncovalent interaction, benchmark measurements of the halogen bond energy are scarce. Here, a combined anion photoelectron spectroscopy and density functional theory (DFT) study of XB in solvated Br−anions is reported. The XB strength between the positively‐charged σ‐hole on the Br atom of the bromotrichloromethane (CCl3Br) molecule and the Br−anion was found to be 0.63 eV (14.5 kcal mol−1). In the neutral complexes, Br(CCl3Br)1,2, the attraction between the free Br atom and the negatively charged equatorial belt on the Br atom of CCl3Br, which is a second type of halogen bonding, was estimated to have interaction strengths of 0.15 eV (3.5 kcal mol−1) and 0.12 eV (2.8 kcal mol−1).
more » « less- NSF-PAR ID:
- 10118711
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 131
- Issue:
- 33
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 11522-11525
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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