Abstract
The local structures around rare-earth ions in rare-earth ultra phosphate glasses (nominally 15RE2O3-85P2O5, mol%, RE = Nd, Sm, Gd, Ho, and Er) and metaphosphate glasses (nominally 25RE2O3-75P2O5, mol%, RE = Nd, Gd, and Er) have been studied by extended X-ray absorption fine structure spectroscopy (EXAFS) at the respective rare-earth LIII edges. the RE-O distance decreases with increasing atomic number of the rare-earth ion for both ultra and metaphosphate glasses. on average, RE-O distances for metaphosphate glasses are shorter than those for ultra phosphate glasses of comparable compositions. There are 7-8 oxygen nearest neighbors in the first co-ordination sphere around rare-earth ions in ultraphosphate glasses and ∼6 oxygens in the first co-ordination sphere around rare-earth ions in metaphosphate glasses. There is no systematic dependence of the RE-O co-ordination number on the atomic number of the rare-earth ions in either compositional series. the second co-ordination shell around rare-earth ions in ultraphosphate glasses consists of phosphorus ions for all but the samarium ultraphosphate glass, with a RE-P distance between 3.53 and 3.85 Å and co-ordination numbers between 3 and 5. No RE-RE correlations were found within a distance of 4.5 Å. © 2005 Elsevier B.V. All rights reserved.
Recommended Citation
M. Karabulut et al., "An EXAFS Investigation of Rare-Earth Local Environment in Ultraphosphate Glasses," Journal of Non-Crystalline Solids, vol. 351, no. 10 thru 11, pp. 795 - 801, Elsevier, Apr 2005.
The definitive version is available at https://doi.org/10.1016/j.jnoncrysol.2005.02.009
Department(s)
Materials Science and Engineering
International Standard Serial Number (ISSN)
0022-3093
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Elsevier, All rights reserved.
Publication Date
15 Apr 2005
Comments
U.S. Department of Energy, Grant DE-AC03-76SF00098