Thermal degradation behaviour of the Ni(II) complex of 3,4-methylenedioxaphenylaminoglyoxime was investigated by TG, DTA, and DTG at a heating rate of 10°C min？1 under dinitrogen. The acquired experimental data shows that the complex is thermally stable up to 541？K. The pyrolytic decomposition process occurs by melting metal complex and metal oxide remains as final product. The energies of the reactions involved and the mechanism of decomposition at each stage have been examined. The values of kinetic parameters such as activation energy ( ), preexponential factor ( ) and thermodynamic parameters such as enthalpy ( ), entropy ( ), and Gibbs free energy ( ) are also evaluated. 1. Introduction vic-Dioximes have attracted extensive attention for many years due to their interesting structural diversity and various potential applications in different areas. Their synthesis, characterization, spectroscopic properties, and reactivity have been the subject of many papers because of their rich physicochemical properties, reactivity patterns, and potential applications in many important chemical processes in the areas such as medicine [1], bioorganic systems [2], catalysis [3], and liquid crystals [4]. Transition metal complexes of vic-dioxime ligands have been widely investigated as analytical reagents as models for biological systems like vitamin B12 [5, 6]. Thermal behaviour of the transition metal derivatives with azomethines (Schiff bases, hydrazones, and oximes) is very important for the researcher in various branches of theoretical and technical chemistry [7–9]. The well-established thermogravimetric analysis (TG), derivative thermogravimetric analysis (DTG), differential thermal analysis (DTA), and derivative thermogravimetric scanning calorimetry (DSC) techniques have been reliably and widely used over many decades in studying thermal behaviour and properties of various types of materials and evaluating the thermal parameters for their degradation processes [10, 11]. The thermal analysis of the compound gives information about its stability and suggests a decomposition pathway. Therefore, kinetic studies have become a crucial point in thermal analysis, in which the main purpose is to determine the mechanism(s) of pyrolysis reaction and to calculate the parameters of the Arrhenius equation. The aims of this research are to study the chemical steps of the investigated degradation and the evaluation of the kinetic and thermodynamic parameters by using (Coats-Redfern) CR, (Horowitz-Metzger) HM, (Van Krevelen) VK, (Broido) B, and (Madhusudanan-Krishnan-Ninan)
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