IR/Raman characterization of Au-mercaptotriazole crystals

Abstract

The aim of this study was a characterization of the crystals of gold complexes based on mercaptotrazole, obtained from solutions with different pH values (2, 4, 7, and 9), using the methods of infrared (IR) and Raman spectroscopy. Both methods provided very useful information on the investigated systems and signalized existence of the Au-S bond in the complexes obtained at pH = 2 and 9. Recorded spectra clearly illustrated the changes that occur in the systems as a consequence of pH change. At the same time, the results also showed that the pyrrole nitrogen atoms stay protonated at pH = 9, which is not in favor of the assumption evolved from the previous UV-vis analysis of possible additional coordination between Au and possible deprotonated nitrogen atoms at this particular pH. Keywords: synthesis; gold-mercaptotriazole (Au-MT); IR and Raman spectroscopy