Authors: Jelena D Zdravković Dejan Poleti Jelena Rogan Nebojša N Begović Vladimir A Blagojević Milica M Vasić Dragica M Minić
Publish Date: 2015/09/18
Volume: 123, Issue: 2, Pages: 1715-1726
Abstract
Thermal degradation of ternary transition metal complex containing tetraanion of pyromellitic acid pyr and ethylenediamine en Ni2en2H2O6pyr·4H2O 1 was investigated under nonisothermal conditions The mechanism of thermal degradation which occurs in three steps was clarified by TG/DSC measurements in conjunction with FTIR spectroscopy and XRPD analysis The complexity of all degradation steps has been revealed using isoconversional methods Dehydration comprises the loss of ten water molecules in a relatively narrow temperature interval resulting in a very complicated reaction mechanism In addition density functional theory calculations have been applied for better understanding of dehydration The second degradation step related to loss of en was separated into two singlestep processes with Fraser–Suzuki function The obtained individual steps were described by Johnson–Mehl–Avrami A2 model and Šesták–Berggren model respectively Validation of the proposed kinetic triplets for individual steps was performed using master plot and PérezMaqueda criteria The third degradation step is related to the fragmentation of pyr ion most likely followed with the release of a number of gaseous products
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