Synthesis, thermal and spectroscopic study of light lanthanide nicotinate, in the solid state

• The lanthanides nicotinates were synthesized.
• The TG–DSC curves provided previously unreported information about thermal behavior.
• The gaseous products released were detected by TG–DSC coupled to FTIR.
• The DFT study was performed.

Characterization, thermal stability and thermal decomposition of light trivalent lanthanide nicotinates, Ln(C6H4NO2)3·nH2O (Ln = La to Gd, except Pm) were synthesized and investigated employing simultaneous thermogravimetry and differential scanning calorimetry (TG–DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry, complexometry and TG–DSC coupled to FTIR. In all the compounds the dehydration occurs in two consecutive steps and the thermal decomposition of the anhydrous compounds occurs in single, two, three or four consecutive steps, with the formation of the respective oxides CeO2, Pr6O11 and Ln2O3 (Ln = La, Nd, Sm, Eu, Gd), as final residue. The results also provided information about the composition, thermal behavior, identification of gaseous products evolved during the thermal decomposition of these compounds. Furthermore, the theoretical and experimental spectroscopic data suggest the possible modes of coordination of the ligand with the metals.