EPR and luminescence of F+ centers in bulk and nanophosphor oxyortho silicates

被引：27

作者：

Cooke, D. Wayne ^{[1
]}

Blair, Michael W. ^{[1
]}

Smith, James F. ^{[1
]}

Bennett, Bryan L. ^{[1
]}

Jacobsohn, Luiz G. ^{[1
]}

McKigney, Edward A. ^{[1
]}

Muenchausen, Ross E. ^{[1
]}

机构：

[1] Los Alamos Natl Lab, Los Alamos, NM 87545 USA

来源：

IEEE TRANSACTIONS ON NUCLEAR SCIENCE | 2008年 / 55卷 / 03期

关键词：

electron paramagnetic resonance; F+ center; luminescence; oxyorthosilicates;

D O I：

10.1109/TNS.2008.922798

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

The main thermally stimulated luminescence glow peak in irradiated oxygrthosilicates; occurs near 360-400 K and has been postulated to comprise an electron trapped at an oxygen vacancy (F+ center). We have used electron paramagnetic resonance spectroscopy to identify this defect in Ln(2)SiO(5) : Ce (Ln = Lu and Y) and show that it consists of a single electron trapped at a non-silicon-bonded oxygen vacancy in both bulk and nanophosphor oxyorthosilicates. Both Lu- and Y-based nanophosphors form seven- and nine-oxygen coordinated structures (P2(1)/c) whereas the bulk phosphors form six- and seven-oxygen coordinated structures (C2/c). In each case the F+ center predominately forms at the larger oxygen site. A typical resonance comprises a single Gaussian line broadened by hyperfine interaction with g-values near the free electron value and hyperfine coupling similar to 0.4 mT. The F+ center can be annealed and radiation-induced, consistent with the thermally stimulated luminescence glow peak behavior.

引用

页码：1118 / 1122

页数：5

共 13 条

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