Synthesis and thermal decomposition of complexes of rare earth bromides with alanine

The complexes of rare earth bromides with alanine, REBr3·3Ala·nH2O (RE=Ce, Pr, Sm, Eu, Gd and Tb, n=3; RE-Dy and Y, n=2.5 Ala=alanine), were prepared and characterized by means of chemical analysis, elemental analysis, molar conductivity, thermogravimetry, IR spectra and X-ray diffraction. The thermal decomposition in N2 of these complexes was studied by means of TG-DTG techniques from ambient temperature, to 1000°C. During heating, the hydrated complexes of Ce, Pr and Y lose waters in one step, but the hydrated complexes of Sm, Eu, Gd, Tb and Dy lose waters in two steps. Then anhydrous complexes lose 2.5 alanine molecules except the complexes of Eu which lose three alanine molecules. Apparently, only the complex of Eu has an intermediate, EuOBr. All complexes finally decompose to oxides.