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2-(5-H/methyl-1H-benzimidazol-2-yl)-4-bromo/nitro-phenol (HL x :X=1-4) ligands and their iron(III) nitrate complexes have been synthesized and characterized. In all of the complexes, the ligands are bidentate, via one imine nitrogen atom and a phenolate oxygen atom. The coordination is completed with a bidentate nitrate anion, and a water molecule. Elemental analysis, molar conductivity, magnetic susceptibility, FT-Raman, FT-IR (mid i.r., far i.r.), UV-visible and as well as quantum chemical calculations performed with CACHE are in agreement with a 1:1 electrolyte structures that are mononuclear, and distorted 5-coordinate square pyramidal. The antimicrobial activities of free ligands, their hydrochloride salts and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) toward nine bacteria, each with multiple, fresh clinical isolates, and the results are compared with those for penicillin-g, ampicillin, cefotaxime, vancomycine, oflaxacin and tetracycline. Antifungal activities were reported for Kluyveromyces fragilis, Rhodotorula rubra, Candida albicans, Hanseniaspora Guilliermondii and Debaryomyces hansenii yeasts, each with multiple isolates, and the results were referenced against nystatin, ketaconazole and clotrimazole antifungal agents. In most cases, the compounds tested showed broadspectrum (Gram + and Gram ) ) activities that were either more active or as potent as the references particularly as antifungal agents.

Lithium bis(oxalate)borate, LiB(C 2 O 4 ) 2 (LiBOB), is one of the most important electrolyte additives for Li-ion batteries (LIBs) due to its numerous advantages such as thermal stability, good solubility in organic solvents, high conductivity, and low cost as well as providing safer operations with superior electrochemical performance compared to conventional electrolyte combinations. However, the use of LiBOB is limited due to slight instability issues under ambient conditions that might require extra purification steps and might result in poorer performances in real systems. Here, we address some of these issues and report the high purity water free LiBOB synthesized with fewer processing steps employing lithium carbonate, oxalic acid, and boric acid as lowcost starting materials, and via ceramic processing methods under protective atmosphere. The physical and chemical characterizations of both anhydrous and monohydrate phases are performed with X-ray powder diffraction (XRPD), Fourier-transform infra-red spectroscopy (FTIR), Raman spectroscopy and scanning electron microscopy (SEM) analyses to determine the degree of the purity and the formation of impurities like LiBOB.H 2 O, HBO 2 and Li 2 C 2 O 4 as a result of the aging investigations performed. Differential thermal analysis (DTA) is applied to determine the optimum synthesis conditions for anhydrous LiBOB and to analyze the water loss and the decomposition of LiBOB.H 2 O. Aging experiments with the water free LiBOB are carried out to evaluate the effect of humidity in the phase changes and resulting impurities under various conditions. The detrimental effect of even slightest humidity conditions is shown, and protective measures during and after the synthesis of LiBOB are discussed. Anhydrous LiBOB could be widely used as an electrolyte additive to improve the overall electrochemical performances for LIBs through development of a protective solid electrolyte interphase (SEI) on the surface of high voltage cathodes and bringing about superior electrochemical properties with increased cycling stability, rate capability and coulombic efficiency, if synthesized, purified, and handled properly before use in real electrochemical systems.

1,3-bis(benzimidazol-2-yl)-2-thiapropane (L) ligand and its zinc halide ZnX 2 (X = Cl, Br, I) complexes have been synthesized. The compounds were characterized using the elemental analysis, molar conductivity, FTRaman, FT-IR (mid i.r., far i.r.), 1 H and 13 C NMR spectra, and quantum chemical calculations performed with Gaussian 03 package program set. The optimized geometries and vibrational frequencies of the ligand and [Zn(L)Cl 2 ] complex were calculated using the DFT/ B3LYP method with a 6-31g(d) basis set. The geometry optimization of [Zn(L)Cl 2 ] yields a slightly distorted tetrahedral environment around Zn ion, while the molecule clearly reveals the Cs symmetry. The molar conductivity data reveals that the complexes are neutral. The ligand is bidentate, via two of the imine nitrogen atoms in the bisimidazole ring units, and together with the monodentate coordination of the two halides to the metal centre.

Zinc acetate solution is sonicated at high power in water and in ethanol in the absence and presence of various peroxides. In the absence of peroxides, the products are zinc oxide and layered hydroxy zinc acetate in water and in ethanol, respectively. Layered basic zinc acetate are prepared for the first time using sonochemical methods. The addition of peroxides alters the reaction mechanisms. In water, insoluble peroxides produce zinc oxides while the water soluble peroxide, i.e. hydrogen peroxide, completely destroyed the structure and casted a doubt on the accepted peroxide initiated mechanism of reactions. In ethanol, peroxide addition caused the reaction mechanism to change and some oxide formation is observed. The reaction mechanism is sensitive to water/ethanol amounts as well as the peroxide to zinc ion mole ratio. Thin zinc oxide wafers (ca. 30nm) with band gaps of 3.24eV were obtained.

The use of LiBOB is limited due to slight instability issues under ambient conditions that might require extra purification steps and might result in poorer performances in real systems. Here, we address some of these issues and report the high purity water free LiBOB synthesized with fewer processing steps employing lithium carbonate, oxalic acid, and boric acid as low-cost starting materials, and via ceramic processing methods under protective atmosphere. The physical and chemical characterizations of both anhydrous and monohydrate phases are performed with X-ray powder diffraction (XRPD), Fourier-transform infra-red spectroscopy (FTIR), Raman spectroscopy and scanning electron microscopy (SEM) analyses to determine the degree of the purity and the formation of impurities like LiBOB.H₂O, HBO₂and Li₂C₂O₄ as a result of the aging investigations performed. Differential thermal analysis (DTA) is applied to determine the optimum synthesis conditions for anhydrous LiBOB and to analyze the water loss and the decomposition of LiBOB.H₂O. Aging experiments with the water free LiBOB are carried out to evaluate the effect of humidity in the phase changes and resulting impurities under various conditions. The detrimental effect of even slightest humidity conditions is shown, and protective measures during and after the synthesis of LiBOB are discussed.

The use of LiBOB is limited due to slight instability issues under ambient conditions that might require extra purification steps and might result in poorer performances in real systems. Here, we address some of these issues and report the high purity water free LiBOB synthesized with fewer processing steps employing lithium carbonate, oxalic acid, and boric acid as low-cost starting materials, and via ceramic processing methods under protective atmosphere. The physical and chemical characterizations of both anhydrous and monohydrate phases are performed with X-ray powder diffraction (XRPD), Fourier-transform infra-red spectroscopy (FTIR), Raman spectroscopy and scanning electron microscopy (SEM) analyses to determine the degree of the purity and the formation of impurities like LiBOB.H₂O, HBO₂and Li₂C₂O₄ as a result of the aging investigations performed. Differential thermal analysis (DTA) is applied to determine the optimum synthesis conditions for anhydrous LiBOB and to analyze the water loss and the decomposition of LiBOB.H₂O. Aging experiments with the water free LiBOB are carried out to evaluate the effect of humidity in the phase changes and resulting impurities under various conditions. The detrimental effect of even slightest humidity conditions is shown, and protective measures during and after the synthesis of LiBOB are discussed.

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