The results show that the Ni(II) complex consists of three Ni(II) ions, two tetradentate (-L)2– units, two coordinated -acetate ions, two coordinated DMF molecules, and two crystallization DMF molecules. <...> All hexacoordinated Ni(II) ions of the complex have a slightly distorted octahedral geometry. <...> The crystal packing of the Ni(II) complex reveals a notable feature of this structure: the formation of an infinite supramolecular 2D layered structure by virtue of intermolecular C—H O hydrogen bonding. <...> Since the highly electronegative oxygen atom strongly affects azomethine nitrogen of N2O2 salen-type bisoxime ligands, thus influencing the N2O2 coordination core and possibly leading to diverse novel structures of the resulted complexes, we began to study monomers where the nitrogen and oxygen environment of the metal center is provided by tetradentate ligands [ 5 ]. <...> This contribution reports a new trinuclear Ni(II) cluster {[NiL(DMF)]2(OAc)2Ni}2DMF (H2L = 4,4-dichloro-2,2-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol) and its structural characterization. <...> X-ray single crystal data were collected on a Bruker Smart 1000 CCD area detector. <...> Molar conductance measurement was carried out on a model DDS-11D type conductivity bridge using a 1.0103 mol L–1 solution in DMF at 25 C. Synthesis of H2L. <...> When the solvent was partially evaporated, several green block-shaped single crystals suitable for X-ray crystallographic analysis were obtained, yield 28.6 %. <...> A single crystal of the Ni(II) complex with approximate dimensions of 0.190.150.12 mm was mounted on a Bruker Smart 1000 diffractometer equipped with an Apex CCD area detector. <...> The complete crystallographic data were deposited as a CIF file in the Cambridge Structural Database (CCDC No. 757708) and are available freely upon request citing the deposition number from the web site: www.ccdc.cam.ac.uk/data_request/cif. <...> IR spectra of H2L and the corresponding Ni(II) complex exhibit several distinguishable bands in the 400—4000 cm–1 region. <...> The O—H stretching frequency of the salentype ligand is expected in the 3300—3800 cm–1 region, but this frequency is displaced to 3424 cm <...>