| Abstract |
The isocyanide trans-[PdBr2(CNC6H4-4-X )(2)] (X =Br, I) and nitrile trans-[PtX2(NCC6H4-4-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). |
