Structural and spectroscopic characterization of a new luminescent NiII complex: bis{2,4‐dichloro‐6‐[(2‐hydroxypropyl)iminomethyl]phenolato‐κ3O,N,O′}nickel(II)

The design and preparation of transition‐metal complexes with Schiff base ligands are of interest due to their potential applications in the fields of molecular magnetism, nonlinear optics, dye‐sensitized solar cells (DSSCs), sensing and photoluminescence. Luminescent metal complexes have been suggested as potential phosphors in electroluminescent devices. A new luminescent nickel(II) complex, Ni(C₁₀H₁₀Cl₂NO₂)₂], has been synthesized and characterized by single‐crystal X‐ray diffraction and elemental analysis, UV–Vis, FT–IR, ¹H NMR, ¹³C NMR and photoluminescence spectroscopies, and LC–MS/MS. Molecules of the complex in the crystals lie on special positions, on crystallographic binary rotation axes. The Ni^II atoms are six‐coordinated by two phenolate O, two imine N and two hydroxy O atoms from two tridentate Schiff base 2,4‐dichloro‐6‐(2‐hydroxypropyl)iminomethyl]phenolate ligands, forming an elongated octahedral geometry. Furthermore, the complex exhibits a strong green luminescence emission in the solid state at room temperature, as can be seen from the (CIE) chromaticity diagram, and hence the complex may be a promising green OLED (organic light‐emitting diode) in the development of electroluminescent materials for flat‐panel‐display applications.