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In each of the zinc(II) complexes bis(acetylacetonato-kappa(2)O,O')(1,10-phenanthroline-kappa(2)N,N')zinc(II), [Zn(C(5)H(7)O(2))(2)(C(12)H(8)N(2))], (I), and bis(acetylacetonato-kappa(2)O,O')(2,2'-bipyridine-kappa(2)N,N')zinc(II), [Zn(C(5)H(7)O(2))(2)(C(10)H(8)N(2))], (II), the metal center has a distorted octahedral coordination geometry. Compound (I) has crystallographically imposed twofold symmetry, with Z' = 0.5. The presence of a rigid phenanthroline group precludes intramolecular hydrogen bonding, whereas the rather flexible bipyridyl ligand is twisted to form an intramolecular C-H...O interaction [the chelated bipyridyl ligand is nonplanar, with the pyridyl rings inclined at an angle of 13.4 (1) degrees]. The two metal complexes are linked by dissimilar C-H...O interactions into one-dimensional chains. The present study demonstrates the distinct effects of two commonly used ligands, viz. 1,10-phenanthroline and 2,2'-bipyridine, on the structures of metal complexes and their assembly.

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Electro-polymerization of orthonitroaniline was carried out on graphite electrode in hydrochloric acid medium. Zinc-nickel alloy deposition was carried out in the presence of polynitroaniline in acid sulphate bath. The bath constituent and bath variables were optimized through Hull cell experiments. The current efficiency and throwing power were measured. High shift of potential towards more cathodic direction was observed in presence of addition agent. Corrosion resistance test revealed good protection of base metal by zinc-nickel coating obtained from the developed electrolyte. SEM photomicrograph shows fine-grained deposit in the presence of addition agent. The consumption of brightener in the lab-scale was 0⋅01 gL -1 for 1000 amp-h.

Inhibition action of seroquel on corrosion of zinc in 0.1 M HCl solution was investigated using weight loss, electrochemical potentiodynamic polarization and impedance spectroscopic techniques. Corrosion inhibition efficiency showed the positive effect with increase in concentration of inhibitor and with the increase in temperature. Results obtained from all the methods are in good agreement with each other. Inhibition effect of inhibitor is due to the adsorption of seroquel molecule on zinc surface from bulk of the solution and the process of adsorption follows Temkin's adsorption isotherm. Potentiodynamic polarization studies revealed that seroquel acts as a mixed type of inhibitor. Corrosion inhibition mechanism is explained by activation and thermodynamic parameters. Surface morphology of the corroded metal was studied by scanning electron microscopic studies and FT-IR spectrum of the corrosion product further confirms the process of adsorption of seroquel on metal surface.