Application of coupled TG-FTIR system in studies of thermal stability of manganese(II) complexes with amino acids.

Detailed thermal analysis of manganese(II) complexes with a-amino acids were carried out. The thermal degradation is multi-stage. Dehydration of complexes is the first mass loss step. Anhydrous compounds are unstable and decompose to Mn₃O₄ in air or to MnO in inert atmosphere. The intermediate solid products were identified by TG method and TG/FTIR combined technique. Among others solid residues, the presence of MnSO₄, MnBr₂ and Mn(CH₃COO)Cl was found. In the gaseous products of decomposition of organic ligand H₂O, NH₃, CO₂, CO, aromatic and non-aromatic hydrocarbons and very probably cyanoacetic acid and dimethyl sulfide occurred. Inorganic ions, i.e. Cl^-, Br^-or So₄ ^2-remain in the solid products of decomposition or are lost as HCl, HBr or SO₂. This revised version was published online in July 2006 with corrections to the Cover Date.