@article{MarmodeeKlerkdeKumkeetal.2008, author = {Marmod{\´e}e, Bettina and Klerk de, Joost and Kumke, Michael Uwe and Ariese, Freek and Gooijer, Cees}, title = {Spectroscopic investigations of complexes between Eu(III) and aromatic carboxylic ligands}, doi = {10.1016/j.jallcom.2007.04.150}, year = {2008}, abstract = {In order to obtain information on the number and symmetry of the different Eu3+ complexes formed with several hydroxybenzoic acids, ultra-low temperature luminescence measurements at 4.7 K were carried out. Hydroxybenzoic acids were used as simple model compounds for metal binding structures in humic substances (HS). Information on the complexes was extracted from high-resolution total luminescence spectra (TLS), which were obtained by scanning through the D-5(0) <-- F-7(0) transition of Eu(III) with a pulsed dye laser and measuring the emission in the wavelength range of the D- 5(0) --> F-7(0) and D-5(0) --> F-7(0) transitions simultaneously. By extracting the crystal field strength parameter N- v(B-2q) from the TLS, it was found that N-v(B-2q) was not directly correlated with the excitation energy. Further, the symmetry of the individual complexes formed was extracted from the experimental data. (C) 2007 Elsevier B.V. All rights reserved.}, language = {en} }