Crystal structure of di­chlorido­(2,2′:6′,2′′-terpyridine-κ³N,N′,N′′)zinc: a redeter­min­ation

The crystal structure of the title compound, [ZnCl₂(C₁₅H₁₁N₃)], was redetermined based on modern CCD data. In comparison with the previous determination from photographic film data [Corbridge & Cox (1956). J. Chem. Soc. 159, 594–603; Einstein & Penfold (1966). Acta Cryst. 20, 924–926], all non-H atoms were refined with anisotropic displacement parameters, leading to a much higher precision in terms of bond lengths and angles [e.g. Zn—Cl = 2.2684 (8) and 2.2883 (11) compared to 2.25 (1) and 2.27 (1) Å]. In the title mol­ecule, the Zn^II atom is five-coordinated in a distorted square-pyramidal mode by two Cl atoms and by the three N atoms from the 2,2′:6′,2′′-terpyridine ligand. The latter is not planar and shows dihedral angles between the least-squares planes of the central pyridine ring and the terminal rings of 3.18 (8) and 6.36 (9)°. The mol­ecules in the crystal structure pack with π–π inter­actions [centroid–centroid distance = 3.655 (2) Å] between pyridine rings of neighbouring terpyridine moieties. These, together with inter­molecular C—H...Cl inter­actions, stablize the three-dimensional structure.