Synthesis, thermal behavior in oxidative and pyrolysis conditions, spectroscopic and DFT studies of some alkaline earth metals p-aminobenzoate complexes using TG-DTA, DSC, PXRD and EGA (TG-FTIR) techniques

Autor: José Augusto Teixeira, Richard P. Fernandes, Guilherme Isquibola, Ana P. S. Gaspari, Antonio E. H. Machado, Flávio J. Caires, Massao Ionashiro
Přispěvatelé: Science and Technology of Paraná, Universidade Estadual Paulista (UNESP), Universidade Federal de Uberlândia (UFU), Federal University of Catalão (UFCAT), Federal University of Mato Grosso
Rok vydání: 2022
Předmět:
Zdroj: Scopus
Repositório Institucional da UNESP
Universidade Estadual Paulista (UNESP)
instacron:UNESP
ISSN: 0040-6031
DOI: 10.1016/j.tca.2022.179184
Popis: Made available in DSpace on 2022-05-01T15:13:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-05-01 p-aminobenzoic acid is a substance widely used in several areas, such as catalysis, biomarkers, magnetic materials, luminescent materials and biological applications. p-aminobenzoate complexes with alkaline earth metal were synthesized and the thermal and pyrolysis behavior was studied using thermoanalytical and spectroscopic techniques. Based on TG/DTG-DTA and EGA results, the thermal decomposition mechanisms of the compounds were proposed under both atmospheres studied. The main gaseous products identified by EGA in both study conditions were H2O, Aniline, CO and CO2. From DSC analysis, it was possible to measure the enthalpies of dehydration and evaluate the phase transitions of the magnesium complex. FTIR data suggest that metal-ligand coordination occurs through carboxylate group by different ways. The coordination modes suggested by experimental FTIR data were supported by DFT study. The X-ray diffraction powder patterns show that the barium compound was obtained in amorphous state, while the other compounds have a crystalline structure. Federal Institute of Education Science and Technology of Paraná, PR São Paulo State University (UNESP) Institute of Chemistry, SP Federal University of Uberlândia (UFU) Institute of Chemistry, MG Graduate Program in Exact and Technological Sciences Physics Institute Federal University of Catalão (UFCAT), GO São Paulo State University (UNESP) School of Science, SP Department of Chemistry / ICET Federal University of Mato Grosso, MT São Paulo State University (UNESP) Institute of Chemistry, SP São Paulo State University (UNESP) School of Science, SP
Databáze: OpenAIRE
Externí odkaz: