Local Structure of Cerium in Aluminophosphate and Silicophosphate Glasses

Abstract

The local structure of cerium in two systematic compositional series of glasses, nominally CeP 3 O 9 -AlP 3 O 9 and CeP 3 O 9 -SiP 2 O 7 , was interrogated using X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) spectroscopy. XPS revealed that, for glasses melted in air, ! 95% of cerium ions are Ce 3+ . This was independently confirmed using X-ray absorption near edge spectroscopy (XANES). Ce K-edge extended X-ray absorption fine structure (EXAFS) has been used to determine the local structure of Ce 3+ . Near the metaphosphate composition, cerium was found to have an average cerium coordination number of~7.0 and an average cerium-oxygen bond length of 2.41 Å . The average cerium coordination number and average cerium-oxygen bond distance were found to increase with decreasing cerium concentration in both compositional series. Rare-earth clustering is suggested based on numerical calculations for glasses containing ! 14 and ! 15 mol% Ce 2 O 3 for the aluminophosphate and silicophosphate series, respectively. II. BackgroundTwo compositional series, centered on cerium metaphosphate, Ce 2 O 3 ·3P 2 O 5 , were chosen to investigate cerium incorporation L.-Q. Chen-contributing editor Manuscript No. 28744.

A review of the structures of oxide glasses by Raman spectroscopy

“…The vibrational properties of structural units are better understood in their structure and 65 bonding as the vibrational spectroscopy cannot be useful as a tool for analyzing their detailed molecular structure. The significant information glass forming ability of 80 various glassy networks was obtained Raman spectroscopic studies in the present review article. The basic borate networks are formed by NBO and BO atoms in tetrahedral 70 borate unit [9].…”

“…A broader 70 and asymmetric band at lower frequency side was assigned with increase of Na 2 O. The peaks due to the isolated diborate groups and the ringtype metaborate groups polymerized by BO 3 and BO 4 units 80 remain unaffected with addition of Al 2 O 3 whereas peak at 770 cm -1 was shifted towards low frequency side in the spectrum. VH spectra showed some more bands at 773, 730 and 670 cm -1 [104].…”

“…1. These are very important for geological applications due to its highly refractory nature [79][80]. Thus, it cannot form the glass easily.…”

The effect of composition on structural, thermal, redox and bioactive properties of Ce-containing glasses

“…For this reason, it is important to investigate with experimental and computational methods the structural role of the doped ions on the glass structure and reactivity. [5][6][7][8][9][10].…”

Effects of La/Ce Ratio on Coloring and Crystallization of MgO‐Al2O3‐SiO2‐TiO2‐CeO2‐La2O3 Glasses

“…In Fig. a, four main peaks can be found and classified into two groups, namely v 0 (883.6 eV) / u 0 (902.5 eV) and v' (886.9 eV) / u' (906.0 eV), which correspond to Ce3d 9 4f 2 O2p 5 and Ce3d 9 4f 1 O2p 6 final states of Ce (III), respectively, as reported in other Ce‐containing materials . Although the existence of Ce (IV) cannot be excluded as a quite small peak u''' (917.2 eV) which is a fingerprint of Ce (IV) is observed, the overall predominant species is Ce (III) for CL0.…”