The effects of heating on the molecular structures of Cd and Co complexes of sulfamethoxazole

Abstract

In this work, the structural changes and stability of sulfamethoxazole and its Co and Cd complexes have been investigated by heating at different temperatures. For this purpose, the infrared spectra (IR) of these samples were recorded in the region between 4000–400 cm −1 after heating the samples at several temperatures at a heating rate of 10°C h −1. At different temperatures, the IR of the heated samples have been compared with those at room temperature. By means of the changes in the fundamental vibrational bands in their IR spectra, the temperature values at which the samples decomposed were determined. As a result of the spectroscopic investigations, it may be concluded that the stability of the complexes is in the order Co>Cd which depends on the second ionization potential of the metals. By using molecular dynamics calculations, the determined bond lengths of the samples at room and decomposing temperatures showed that the experimental results are consistent with theoretical calculations.