Local coordination of europium(III) in poly(ethylene oxide) and poly(propylene oxide)

✍ Scribed by L.D. Carlos; A.L.L. Videira; M. Assunção; L. Alcácer

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 461 KB
• Volume: 40
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(95)00154-7

✦ Synopsis

The luminescence spectra of (PEO/PPO),EuBr, , with n = 3-80, were recorded and the corresponding excitation and emission lines assigned to the 'F,_, + 'G,, 'L,, 'D,_, and to the 'D, 1 -t 'F,_4 transitions, respectively. The emission energies were used for investigating the local coor- dination of europium(II1) in these polymer electrolytes. The nearest ligands charge distribution was specified in terms of a mean radius for the Eu 3+ first coordination shell, and the results found for different concentrations of the ion, 2.3-2.7 A, are compatible with known data. The local-field interaction model, the polarization behavior of the 'D,, --t 'F, transition, certain moment operators, and the optical activity of the 'F,,,,, components, permitted to assign the approximate local symmetry of the Eu3+ in PEO/PPO electrolytes to the C,, point group.