[N,N?-Bis(5-chlorosalicylidene)-1,3-diaminopropane]nickel(II) [Ni(C17H14N2O2Cl2)] 1 and [N,N?-Bis(5-chlorosalicylidene)-1,3-diaminopropane]nickel(II) dihydrate [Ni(C17H14 N2O2Cl2).2(H2O)] 2 were synthesized, and their crystal structures were determined. Compound 1 is monoclinic, space group C2/c, a = 21.063(4), b = 8.151(1), c = 9.421(2) Å, ? = 94.16(1)°, V = 1613.2(5) Å3, Z = 4 and Dc = 1.680 g cm-3. Compound 1 contains a crystallographic twofold axis, and the whole molecule is not planar. The two Schiff base moieties, which in themselves are planar, are twisted with respect to one another. The least-squares planes through each half of the molecule are inclined at an angle of 29.1(1)°. The Ni atom is in a square-planar environment. The Ni - N and Ni - O distances are 1.958(2) and 1.910(2) Å, respectively. Compound 2 is orthorhombic, space group Pnma, with a = 7.892(1), b = 23.396(2), c = 9.992(1) Å, V = 1846.3(3) Å3, Z = 4 and Dc = 1.597 g cm-3. Compound 2 has crystallographic mirror symmetry, and again, the whole molecule is not planar. The two planar Schiff base moieties inclined at an angle of 38.7(1)°. The Ni atom is in a distorted octahedral geometry and coordinated by the donor atoms of the ligand in the horizontal plane, and the coordination sphere is completed by O atoms of two water molecules
