الفهرس 
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Abstract
The scope of the present thesis is to study the binary complexes of Cu(II), Ni(II), Mn(II) and Cd(II) ions with some ligands containing thiosemicarbazone. These are pyridine-2-carboxaldehyde-N(4)-o-cholorophenyl thiosemicarbazone(HL1), pyridine-2-carboxaldehyde-N(4)-p-nitrophenyl thiosemicarbazone (HL2) and pyridine-2-carboxaldehyde-N(4)-o-methoxyphenyl thiosemicarbazone (HL3). The secondry ligands used in preparation of the mixed ligand complexes are sodium dimethyl dithiocarbamate trihydrate (Nadtc.3H2O), sodium pipridine dithiocarbamate dihydrate (Napipdtc.2H2O) and 8-hydroxyquinoline (quin).
The study involves synthesis of the complexes and characterization of their structure using elemental analysis, magnetic susceptibility measurements, electronic and infrared spectra as well as molar conductance measurements. The thesis also includes a study of thermal behavior, kinetic and thermodynamic parameters of the binary and mixed ligand complexes. Antibacterial activites against bacterial species (Bacillus cereus, Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomons aeruginosa, and Serratia marcescens) as well as the antifungal effects against fungal species (Candida albicas, Geotrichum candidum, Trichophyton rubrum, Fusarium oxysporum, Scopulariopsis brevicaulis, and Aspergillus flavus) have been studied.
This thesis consists of six chapters. In what follows, a brief description of each chapter included in the present thesis is given:
1. The first chapter reports a general literature survey of some pyridine-2-carboxaldehyde thiosemicarbazone Schiff bases metal complexes.
2. The second chapter includes the experimental details for the preparation of pyridine-2-carboxaldehyde-N(4)-o-cholorophenyl thiosemicarbazone (HL1), pyridine-2-carboxaldehyde-N(4)-p-nitrophenyl thiosemicarbazone (HL2) and pyridine-2-carboxaldehyde-N(4)-o-methoxy phenyl thiosemicarbazone (HL3) ligands and their binary complexes with Cu(II), Ni(II), Mn(II) and Cd(II) ions as well as their mixed ligand complexes using sodium dimethyl dithiocarbamate trihydrate (Nadtc.3H2O), sodium pipridine dithiocarbamate dihydrate (Napipdtc.2H2O) and 8-hydroxyquinoline (quin) ligands. The working procedure and equipments used for measurements are also described. The method used for calculation of the magnetic susceptibility and its correction is also included in this chapter.
3. The third chapter reports the characterization of the isolated binary complexes of Cu(II), Ni(II), Mn(II) and Cd(II) ions. The studies given in this chapter reveals the following conclusions:
The ligands used possess thiol-thione tautomerism in solution; they have a higher contribution of the thione form in the solid form.
The data of the analysis of the binary complexes show that the binary complexes have 1:1 and 1:2 (metal: ligand) ratio.
The ligands (HL1), (HL2) and (HL3) act as monobasic tridentate ligands and they can coordinate to metal ions via the azomethine nitrogen, the pyridyl nitrogen and thiolate sulfur atoms.
The molar conductance values of all the prepared binary complexes in (1x10-3 M) DMF solutions indicating the nonelectrolytic nature of these complexes.
Electronic spectra and magnetic susceptibility measurements indicate that all Cu(II) binary complexes have square planar geometry, all Ni(II) binary complexes have square-planar geometry and all Mn(II) binary complexes have octahedral geometry.
The thiosemicarbazone ligands and their binary complexes were screened for their in-vitro antibacterial and antifungal activity.
4. The fourth chapter reports the characterization of the mixed ligand complexes of Cu(II), Ni(II), Mn(II) and Cd(II) ions with dtc, pipdtc or quin secondary ligands. The studies given in this chapter reveals the following conclusions:
The data of the analysis of the mixed ligand complexes show that the molar ratio is (1:1:1) (metal: thiosemicarbazone ligand: secondary ligand) ratio.
The dtc and pipdtc ligands act as a monobasic bidentate ligand and they can coordinate to metal ions through two sulfur atoms while the quin ligand acts as a monobasic bidentate ligand and it can coordinate to metal ions through both nitrogen and oxygen atoms.
The molar conductance values of all the prepared mixed ligand complexes in (1x10-3 M) DMF solutions indicate the nonelectrolytic nature of these complexes.
Electronic spectra and magnetic susceptibility measurements indicate that all of the prepared mixed ligand complexes are having octahedral geometries.
5. The fifth chapter includes the equations used in the calculation of kinetic and thermodynamic parameters for the obtained binary complexes. Moreover, it includes the results and discussion of thermogravimetric analysis, kinetic and thermodynamic parameters of the binary complexes. The study provides an investigation of the way by which thermal decomposition of the complexes take place. The kinetic analysis of the thermal decomposition of the binary complexes in nitrogen atmosphere was performed under nonisothermal conditions and over the temperature range from room temperature to 750 oC, using TGA and DTG techniques. The kinetic parameters n (order of decomposition), E (activation energy) and Z (pre-exponential factor or collision factor) as well as thermodynamic functions ΔG (free energy of activation), ΔH (enthalpy of activation) and ΔS (entropy of activation) were determined and discussed. This study leads to the following conclusion: Cd(II) binary complexes with (L2) and (L3) ligands are thermally more stable than Cu(II), Ni(II) and Mn(II) binary complexes with (L2) and (L3) ligands while Mn(II) binary complex with (L1) ligand is thermally more stable than Cu(II), Ni(II) and Cd(II) binary complexes with (L1) ligand. [Cd(L2)Cl] is the most stable binary complex.
6. The sixth chapter includes the thermal studies of the mixed ligand complexes, including a full study of the thermal degradation of the mixed ligand complexes, the calculations and discussion of the kinetic and thermodynamic parameters of the different decomposition steps. This study leads to the following conclusions:
Cu(II) ion forms most stable dtc, pipdtc, quin mixed ligand complexes when (L1), (L2) or (L3) are employed as thiosemicarbazone containing ligands.
The following stability order pipdtc > dtc > quin is shown for all Cu(II), Ni(II) and Cd(II) mixed ligand complexes.
Generally in most cases Cu(II) mixed ligand complexes with pipdtc, dtc or quin are most thermally stable compared to the Ni(II) and Cd(II) mixed ligand complexes with pipdtc , dtc or quin.
[Cu(L2)(pipdtc)(H2O)] is the most thermally stable mixed ligand complex and is the most thermally stable complex for all the synthesized binary and mixed ligand complexes in our study.