Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10631336 | Journal of Non-Crystalline Solids | 2005 | 7 Pages |
Abstract
Synthesis, spectroscopic studies, prediction of the structure and thermal decomposition of the La(3-OHpic)3 · 3H2O and Nd(3-OHpic)3 · 3H2O (3-OHpic = 3-hydroxypicolinic acid) complexes are described. Elemental analysis and the IR vibrational data are consistent with the complex formulae. The absorption spectra in ethanol of the La(3-OHpic)3 · 3H2O and Nd(3-OHpic)3 · 3H2O show maximum absorptions at 214 and 211 nm, respectively, which are shifted to 225 nm in the free ligand. The ab initio method RHF/STO-3G/ECP(MWB52) was used to optimize the geometry and the INDO/S-CI model for calculating the electronic spectra of these complexes. A good agreement between theoretical and experimental UV absorption spectra has been obtained. The thermal decomposition was studied by non-isothermal thermogravimetry. Thermal decomposition reactions of the complexes La(3-OHpic)3 · 3H2O and Nd(3-OHpic)3 · 3H2O are best described by R2 and R3 kinetic models.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
M.E. de Mesquita, L.S. Barreto, M.L. Santos, R.O. Freire,