Using as example the [Fe(bpca)(μ-bpca)Gd(NO)]×4CHNO×CHOH system, where Hbpca=bis(2-pyridilcarbonyl)amine), we perform the analysis of bonding components inside the d and f coordination units and between molecular entities from crystal. Aside the nominal long-range interactions between molecular components of the crystal, we considered that the bonding inside the coordination units is also not a covalent regime. We performed Density Functional Theory (DFT) calculations, with plane-waves (PW), in band-structure mode, and with atom-centred bases, by molecular procedures.
View Article and Find Full Text PDFThe present work describes the synthesis of a new triazole based ligand 3-(3,5-dimethyl-1-pyrazol-1-yl)-1-methyl-1-1,2,4-triazole (LM) and demonstration of its coordination diversity giving rise to a family of seven new coordination complexes, namely: [Ni(LM)](ClO)·CHOS (5), [Co(LM)](ClO)·(CH)O (6), [Cd(LM)Cl] (7), [Cu(LM)NO]NO (8), [Fe(LM)](BF) (9), [Zn(LM)](BF) (10) and [Zn(LM)NO]NO (11), whose crystal structure was determined by single-crystal X-ray diffraction. Cytotoxic activity was evaluated against the MDA-MB-468 cancer cell line, which serves as a model for triple-negative breast cancer, and compared to the precursor molecule (L), as well as their coordination complexes (HO){[NiL](ClO)} (1), [CoL](ClO)·2HO (2), [CdLCl] (3) and [CuL](NO) (4), for which the crystal structure was earlier determined. Notably, cadmium complexes 3 and 7 exhibit remarkable cytotoxicity and demonstrated a high selectivity index towards cancer cells when compared to peripheral blood mononuclear cells.
View Article and Find Full Text PDFFour mononuclear complexes (HO){[NiL](ClO)} (), [CoL](ClO)·2HO (), [CdLCl] () and [CuL](NO) () have been prepared employing a newly synthesized 1,2,4-triazole ligand: 3-(3,5-dimethyl-1-pyrazol-1-yl)-1-1,2,4-triazole (). The structures of the complexes, which crystallized in (), (), (), and (), are reviewed within the context of the cooperative effect of the hydrogen bonding network and counter anions on the supramolecular formations. Moreover, within the framework of biological activity examination, these compounds showed favorable antibacterial performances compared to those of various species of bacteria, including both Gram-positive and Gram-negative strains.
View Article and Find Full Text PDFSesquipedalian mud and burnt bricks (second to third century AD) were excavated from the Roman city of Romula located in the Lower Danube Region (Olt county, Romania). Along with local soils, bricks are investigated by petrographic analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), electron microscopy (SEM/EDX), X-ray microtomography (XRT), thermal analysis (DTA-TG), Mӧssbauer spectroscopy, magnetometry, colorimetry, and mechanical properties assessment. The results correlate well with each other, being useful for conservation/restoration purposes and as reference data for other ceramic materials.
View Article and Find Full Text PDFZnO nanoparticle-based multifunctional coatings were prepared by a simple, time-saving microwave method. Arginine and ammonia were used as precipitation agents, and zinc acetate dehydrate was used as a zinc precursor. Under the optimized conditions, flower-like morphologies of ZnO aggregates were obtained.
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