Molecular helicity in inorganic complexes: The crystal and molecular structure of 2,6-diacetylpyridine bis(6-chloro-2-pyridylhydrazone) silver(I) hexafluorophosphate dimer

The crystal and molecular structure of the complex [Ag₂L¹₂][PF₆]₂ [L¹ = 2,6- diacetylpyridine bis(6-chloro-2-pyridylhydrazone)] have been determined. The cation is binuclear with each silver in a distorted four-coordinate environment, showing weak interactions with a fifth ligand and with a short Ag-Ag distance of 3.142 Å. The two equivalent ligands are wrapped around the binuclear core in a double-helical array. This is stabilized by π-stacking interactions between parallel pyridyl rings. The double-helical array is generated in a spontaneous self-assembly process which is dictated by the relative acceptor properties of the silver(I) ion and the donor properties of the ligand.