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Updated: Apr 19, 2026
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Crystal structure of catena-poly[[potassium-tri-μ-di-methyl-acetamide-κ(6) O:O] iodide]
Cezar-Catalin Comanescu1, Allen G Oliver1
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556-5670, USA.
Abstract:
The structure of catena-poly[[potassium-tri-μ-di-methyl-acetamide-κ(6) O:O] iodide], {[K(C4H9NO)3]I} n , at 120 K has trigonal (P-3) symmetry. The structure adopts a linear chain motif parallel to the crystallographic c axis. Two crystallographically independent K(+) cations are present in the asymmetric unit located on threefold rotoinversion axes at [0, 0, 0] and [0, 0, 1/2] and are bridged by the O atoms of the acetamide moiety. This is an example of a rare μ2-bridging mode for di-methyl-acetamide O atoms. The iodide counter-ion resides on a threefold rotation axis in the channel formed by the [K(C4H9NO)](+) chains.
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