Cyclic voltammetry, chronoamperometry, chronocoulometry, rotating disc electrode, and electrochemical quartz crystal microbalance techniques were used to study redox properties of dithiocarbamate lithium salts solutes in dimethylsulfoxide or acetonitrile environment. The investigated compounds were synthesized from N, N'-dimethylethylenediamine, to which one or two dithiocarbonyl groups were attached by reacting with CS2 in alkaline solutions.
Voltammetric studies of the oxidation of these moieties showed the irreversible, though reproducible, broad peak at scan rates ranging from 0.01 to 0.5 V s-1. The chronoamperometric and rotating disc electrode experiments confirmed the consumption of le/active group. Upon changing the electrode from Pt to glassy carbon only slight shift of the anodic peak potential, and negligible current change has been observed. These findings were interpreted as an indication, that the electrode materials do not have a direct influence on the formation of the dithiocarbamate radicals (for example, via chemisorption) and in further dimerization of these radicals to thiuram disulfide. The latter process is assumed to proceed at a rate close to the diffusion limit. The calculated symmetry coefficients were distinctly lower than 0.5; the value predicted by the Butler-Volmer theory. Such an outcome implies that the potential range, where the reaction proceeds, is much more positive than the standard potential of the reaction. The oxidation of the compound containing two electroactive groups led to the formation of a wide spectrum of diverse disulfide compounds differing one from another by the molecular weight (evidenced through different diffusion coefficients) owing to the various degree of the coupling.
The reductive S-S bond fission reactions (thiuram disulfides reduction), brought about by driving the electrode potential to the negative range, were found to be affected by the electrode material. At identical scan rates, the reduction peak potential at platinum is shifted in the negative direction with respect to that of the glassy carbon electrode. This observation is interpreted as being caused by the chemical interaction of thiuram disulfides with Pt prior to electron transfer. The interaction might not be very strong because of steric hindrance (C-S-S-C dihedral angle is ca. 94°) and needs for some structure reorganization (mainly bond stretching) in order to adjust to a distance between the Pt atoms.

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CONTENTS
The symbols

1. INTRODUCTION
1.1. Major objectives of this monograph

2. PHYSICO-CHEMICAL PROPERTIES OF DITHIOCARBAMATES
2.1. Acidic dissociation
2.2. Stability
2.3. Complexing properties
2.4. Structure
2.5. Chemical oxidation

3. ELECTROCHEMICAL CKIDATION

4. REACTIONS OF THIYL RADICALS AND DISULFIDE ANION RADICALS

5. APPLICATION OF DITHIOCARBAMATES AND THIURAM DISULFIDES

6. IONIZATION POTENTIALS, ELECTRON AFFINITIES, AND ELECTROCHEMICAL POTENTIALS
6.1. Ionization potentials
6.2. Electron affinity
6.3. Electrochemical potentials

7. REDOX REVERSIBILITY
7.1. Definition of chemical and electrochemical redox reversibility
7.2. The principle of microscopic reversibility

8. SYNTHESIS AND CHEMICAL ANALYSIS OF DITHIOCARBAMATES
8.1. An overview
8.2. Simple dithiocarbamates
8.3. Dithiocarbamate polymers

9. BACKGROUND OF THE EXPERIMENTAL TECHNIQUES
9.1. Chronoamperometry and chronocoulometry
9.1.1. Chronoamperometric reversal experiments
9.1.2. Chronocoulometric reversai experiments
9.1.3. Chronoamperometry of films
9.2. Rotating disk electrode
9.3. Cyclic voltammetry
9.3.1. Nernstian (reversible) systems
9.3.2. Totally irreversible systems
9.4. Convolutive or semi-integral techniques
9.5. Frumkin correction
9.6. Electron transfer at electrodes - classical approach
9.6.1. Outer-sphere electron transfer theory. The Marcus-Hush theory
9.6.2. Dissociative electron transfer theory. The Saveant theory
9.7. Theoretical standard ratę constant
9.8. Theoretical transfer coefficient
9.9. The electrochemical quartz crystal microbalance
9.9.1. Theoretical background

10. ELECTRODES AND APPARATUS
10.1. Electrode coating procedure
10.2. Apparatus and procedures
10.3. The electrochemical quartz crystal microbalance. Experimental setup
10.4. Calibration of the EQCM

11. COMPUTATION METHODS

12. STRUCTURE MODELING

13. EVALUATION OF THE STANDARD POTENTIALS

14. CYCLIC VOLTAMMETRY
14.1. Oxidation of model compounds
14.2. Reductive cleavage of model thiuram disulfides
14.3. Polymer compounds

15. POTENTIAL STEP EXPERIMENTS
15.1. Chronoamperometry
15.2. Chronocoulometry
15.3. Rotating disc electrode

16. IONIC TRANSPORT IN CAST FILMS

17. ELECTRON TRANSFER KINETICS
17.1. The convolution analysis
17.2. The analysis based on the peak position
17.3. The analysis based on the peak height
17.4. The intrinsic rate constant

18. DISCUSSION

REFERENCES
SUMMARY IN POLISH