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Updated: Jan 23, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Four-Center Nodes: Supramolecular Synthons Based on Cyclic Halogen Bonding
Mariya A Kryukova1, Daniil M Ivanov1, Mikhail A Kinzhalov1
1Institute of Chemistry, Saint Petersburg State University, Universitetskaya Nab. 7/9, 199034, Saint Petersburg, Russian Federation.
Abstract:
The isocyanide trans-[PdBr2 (CNC6 H4 -4-X')2 ] (X'=Br, I) and nitrile trans-[PtX2 (NCC6 H4 -4-X')2 ] (X/X'=Cl/Cl, Cl/Br, Br/Cl, Br/Br) complexes exhibit similar structural motif in the solid state, which is determined by hitherto unreported four-center nodes formed by cyclic halogen bonding. Each node is built up by four Type II C-X'⋅⋅⋅X-M halogen-bonding contacts and include one Type I M-X⋅⋅⋅X-M interaction, thus giving the rhombic-like structure. These nodes serve as supramolecular synthons to form 2D layers or double chains of molecules linked by a halogen bond. Results of DFT calculations indicate that all contacts within the nodes are typical noncovalent interactions with the estimated strengths in the range 0.6-2.9 kcal mol-1 .
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