Synthesis characterization and X-ray structure of copper(II) and nickel(II) complexes of N,N,N′,N′-tetrakis(2-benzimidazolylmethyl)-1,2-ethanediamine

This work describes the synthesis of octahedral copper(II), [Cu(L)](2+) (1) and nickel(II), [Ni(L)](2+) (2) complexes of a potentially hexa-coordinating ligand L (L = N, N, N',N'-tetrakis (2-benzimidazolylmethyl) - 1,2-ethanediamine), and characterized by single crystal X-ray diffraction method. The complex [Cu(L)](ClO4)(2) crystallizes in the monoclinic system with the space group C2/c, a = 17.528(4), b = 10.895(2) and c = 18.986(4) angstrom, beta = 96.54(3)degrees. The complex [Ni(L)](ClO4)(2)center dot 4H(2)O crystallizes in the orthorhombic system with the space group P2(1)2(1)2(1), a = 11.952(2), b = 15.317(2), c = 22.517(5) angstrom, alpha = beta = gamma = 90 degrees. Room temperature magnetic moment studies reveal that both the complexes are paramagnetic with mu(eff) 2.03 and 2.98 B.M. for copper(II) and nickel(II) complexes respectively. Room temperature EPR studies on polycrystalline powder material of copper(II) complex give <g(av)> = 2.028 as well as in solution state <g(av)> = 2.025.