Electron spin resonance of diluted solid solutions of Gd{sub 2}O{sub 3} in CeO{sub 2}
- Secao de Engenharia Meca-hat nica e de Materiais, Instituto Militar de Engenharia, Praca General Tiburcio, 80 Praia Vermelha, CEP: 22290-270 Rio de Janeiro, RJ (Brazil)
- Instituto de Fisica, Universidade do Estado do Rio de Janeiro, 20550-013 Rio de Janeiro, RJ (Brazil)
Electron spin resonance spectra of Gd{sup 3+} in diluted solid solutions of Gd{sub 2}O{sub 3} in CeO{sub 2} have been studied at room temperature for Gd concentrations between 0.01 and 1.00mol%. While in the case of Mn{sup 2+}:CeO{sub 2} samples, both the linewidth and the line intensity go through a maximum between 0.2 and 0.4% Mn and then start to decrease, in the case of Gd{sup 3+}:CeO{sub 2} samples the linewidth and the line intensity increase monotonically with the dopant concentration. This as taken as evidence that in Gd{sub 2}O{sub 3}-CeO{sub 2} diluted solid solutions there are no clustering effects similar to the ones observed in Mn:CeO{sub 2} solid solutions. It is not clear why clustering effects are present in Mn:CeO{sub 2} solid solutions and not in Gd:CeO{sub 2} solid solutions; however, it seems reasonable to assume that this is due to the fact that the ionic radius of Mn{sup 2+} (81 pm) is about 25% smaller that that of Gd{sup 3+} (107.8pm). In any case, the fact that Gd:CeO{sub 2} solid solutions do not exhibit clustering effects means that ESR linewidth data can be used to estimate the concentration of Gd in CeO{sub 2} samples, as it is possible to do in several solid solutions of paramagnetic ions in ceramic materials. The results also suggest that the range of the exchange interaction between Gd{sup 3+} ions in CeO{sub 2} is about 0.89nm.
- OSTI ID:
- 20725986
- Journal Information:
- Journal of Solid State Chemistry, Vol. 178, Issue 6; Other Information: DOI: 10.1016/j.jssc.2005.04.004; PII: S0022-4596(05)00155-6; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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