الفهرس 
Molecular computational calculation
Vibrational calculation and thermodynamic parameters ofOnly 14 pages are availabe for public view
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Abstract
This thesis is focused on the preparation and characterization of new complexes of 2-picolinoyl-N-(pyridin-2-yl)hydrazine-1-carbothioamide
(H2L1); N-(2-picolinoylhydrazine-1-carbonothioyl)benzamide (H2L2); 2-(2-(2-aminothiazol-4-yl)acetyl)-N-(pyridin-2-yl)hydrazine-1-carbothioamide (H2L3) and N-(2-(2-(2-aminothiazol-4-yl)acetyl)hydrazine-1-carbonothioyl)benzamide (H2L4) with Cr(III), Mn(II), Fe(III), Co(II),
Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) and U(VI)O2 2+ metal ions using elemental analyses, thermal (TGA and DTGA) and different spectroscopic techniques such as spectral (IR, UV-Visible and 1H NMR), XRD and magnetic measurements. Also, the molecular computational calculation, biological activity and molecular docking studies were carried out. The proposed chemical formulae of the ligands and their metal complexes are in good agreement with the stoichiometries concluded from their analytical data of carbon, hydrogen, nitrogen, sulfur, chloride and metal contents. In addition, most of complexes have high melting points (>300˚C) and insoluble in most organic solvents. The coordination sites of the ligand, the nature of metal-ligand bonds, the nature of the acetate groups and the existence of the solvated molecules have been elucidated using FT-IR spectra. Different modes of chelation for the investigated ligands are suggested based on the careful comparison between the spectra of the ligands and their metal complexes. Furthermore, the 1H-NMR spectra of the diamagnetic Zn (II) complex of H2L2, Cd(II) complexes of H2L1 and H2L2, Hg(II) complex of H2L2 and all U(VI)O2 complexes of the four ligands are helpful to detect the molecular structure. The geometries are suggested of the prepared complexes based on the data evaluated from spectral and magnetic measurements; [Zn2(L1)2], [Cd2(L1)(H2O)2Cl2], [Hg(HL2)Cl2].H2O, [Zn2(L3)2].H2O, [Cd(HL3)Cl], [Hg(HL3)Cl], [Co(HL4)Cl].2H2O, [Zn(L4)].H2O, [Cd(HL4)Cl] and [Hg2(L4)Cl2] complexes which have tetrahedral structures. While [Mn2(H2L2)(H2O)Cl4].2H2O complex showed mixed tetrahedral and octahedral geometries. Also, [Cu(HL2)(H2O)Cl] exhibited a squrae plannar geometry. Furthermore, [Zn(L2)(H2O)].H2O and [Cd(HL2)(H2O)2Cl].H2O displayed square pyramidal geometries. Finally, all other complexes afforded octahedral geometries. Also, good information about the geometry and crystal lattice system, lattice parameters of [Cu2(HL1)2(H2O)2Cl2].H2O and [Cu(HL2)(H2O)Cl] complexes have been elucidated using the powder X-ray diffraction pattern, confirming an octahedral geometry for [Cu2(HL1)2(H2O)2Cl2].H2O complex and a square planar geometry for [Cu(HL2)(H2O)Cl] complex. Detailed thermal analysis for the prepared complexes was performed in the temperature range 14-800 ˚C. The thermograms show the decomposition steps after which a constant weight is observed, corresponding to the remaining part of the complex. Additionally, in order to assess the influence of the structural properties of the ligands and the type of the metal on thermal behavior of the complexes, the order (n) and the heat of activation (Ea) of the various decomposition stages are determined from the TGA and DTGA using Freeman-Carroll, Horowitz-Metzger, Dharwadkar-Karkhanavala, Coats-Redfern and Broido methods. Also, the thermodynamic parameters of activation (ΔH*, ΔS* and ΔG*) had been calculated by Erying equation. Finally, the antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans bacterial strains, antioxidant activity using superoxide dismutase like activity and diphenyl picryl hydrazyl free radical scavenging activity and the molecular docking for H2L1-H2L4 and their metal complexes towards the three-dimensional complex structure of E. coli (PDB ID: 1C14), S. aureus (PDB ID: 3BL6) and C. albicans (PDB ID: 1IYL) had been studied.