Co 3 O 4 and ZnO nanoparticles with different morphologies were synthesised by the thermal decomposition of single source precursors obtained from readily available and eco-friendly starting materials (hexamethylenetetramine and metal nitrates). The precursors, which were characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction and thermal gravimetric analysis, were calcined at 500ºC for 2 h, and the oxide samples obtained were characterized by FTIR, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and nitrogen physisorption. XRD showed that the oxides obtained were crystalline and free of extraneous impurity phases. The morphology of the nanoparticles obtained changed from cube-like (Co 3 O 4) to hexagonal-prism like morphology (ZnO), while the particle size increased from 19.6 to 64.5 nm, respectively. The method used simple and cheap precursors, which should make it suitable for large-scale synthesis.

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A nickel(II) complex with hexamethylenetetramine and thiocyanate ion as coligands has been synthesized and characterised by infrared spectroscopy and ultraviolet-visible spectroscopic techniques. The crystal structure of the complex was determined by single crystal X-ray diffraction and the ligands were found to coordinate terminally through N-atoms. The ligand and the complex were screened for their activity against resistant strains of bacteria (Salmonella enteric, Shigella flexneri, Escherichia coli, and Staphylococcus aureus) and fungi (Candida albicans, Candida krusei, Candida parapsilosis, and Candida neoformans).

Reaction of zinc acetate, potassium thiocyanate and the ligand 3-ampy gave the discrete tetrahedral complex [Zn(NCS) 2 (3-ampy) 2 ] in which 3-ampy chelates in a monodentate fashion through its pyridine-N atom. It was characterized by single crystal X-ray diffraction, infrared, and elemental analysis. Density Functional Theory calculations were performed in order to gain insights into the role of weak molecular interactions in the complex that influence the self-assembly process and crystal packing. X---H (X = H, C, N and S) inter-actions. S-H interactions (30.2%) were found to be the main interactions that hold the molecules in the crystal structure. Furthermore, the thermolysis of the complex was studied in order to evaluate whether it was suitable as a precursor for zinc sulphide.

The complexes of Manganese(II) with 1,10-phenanthroline using the nitrate, thiocyanate and dicyanamide as co-ligands have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermal analysis and room temperature magnetic susceptibility measurements. The magnetic moments of the complexes are consistent with high spin (d5) octahedral geometry. Single-crystal X-ray analysis confirmed the complexes to be [Mn(Phen)2(NO3)2] (1), [Mn(Phen)2(N3)2)] (2), and [Mn(Phen)2(dca)2)] (3). Complexes 1 and 2 crystallize in an orthorhombic crystal system with space group Pbcn while complex 3 crystallizes in the monoclinic crystal system with space group P21/c. The complexes have been screened for in vitro antibacterial and antifungal activities by the disc diffusion method. The minimum inhibitory concentration values indicate that the complexes showed greater activity against the fungi strains tested compared to that of the reference antifungal.