TY - JOUR
T1 - X-ray storage luminescence of BaFCl:Eu 2+ single crystals
AU - Chen, Wei
AU - Kristianpoller, N.
AU - Shmilevich, A.
AU - Weiss, D.
AU - Chen, R.
AU - Su, Mianzeng
PY - 2005/6/16
Y1 - 2005/6/16
N2 - Temperature behaviors of X-ray luminescence (XL), photoluminescence (PL), photostimulated luminescence, and thermoluminescence (TL) were studied in BaFCl:Eu 2+ single crystals from room temperature to liquid nitrogen temperature. Six emissions at 275, 315, 365, 385, 435, and 500 nm were observed in the XL spectra and are attributed to Cl excitons, V k(Cl 2 -), the 4f 65d 1 ( 2e g) → 4f 7 ( 8S 7/2) transition of Eu 2+, and oxygen vacancies, respectively. Three emission peaks at 315, 365, and 390 nm were observed in the PL and TL measurements. These three emissions are from the transitions of 4f 7 ( 6I 7/2) → 4f 7 ( 8S 7/2), 4f 7 ( 6P 7/2) → 4f 7 ( 8S 7/2), and 4f 65d 1 ( 2 eg) → 4f 7( 8S 7/2) of Eu 2+, respectively. In our measurements, we observed that the emission of Eu 2+ increases in intensity upon β-irradiation and did not see any signals related to Eu 3+ ions, which indicates that Eu 2+ ions might not be oxidized to Eu 3+ upon X-ray or β-irradiation. Instead, the color centers, Cl excitons, and oxygen defects are created and are stable at room temperature, and they might play a key role in the storage luminescence.
AB - Temperature behaviors of X-ray luminescence (XL), photoluminescence (PL), photostimulated luminescence, and thermoluminescence (TL) were studied in BaFCl:Eu 2+ single crystals from room temperature to liquid nitrogen temperature. Six emissions at 275, 315, 365, 385, 435, and 500 nm were observed in the XL spectra and are attributed to Cl excitons, V k(Cl 2 -), the 4f 65d 1 ( 2e g) → 4f 7 ( 8S 7/2) transition of Eu 2+, and oxygen vacancies, respectively. Three emission peaks at 315, 365, and 390 nm were observed in the PL and TL measurements. These three emissions are from the transitions of 4f 7 ( 6I 7/2) → 4f 7 ( 8S 7/2), 4f 7 ( 6P 7/2) → 4f 7 ( 8S 7/2), and 4f 65d 1 ( 2 eg) → 4f 7( 8S 7/2) of Eu 2+, respectively. In our measurements, we observed that the emission of Eu 2+ increases in intensity upon β-irradiation and did not see any signals related to Eu 3+ ions, which indicates that Eu 2+ ions might not be oxidized to Eu 3+ upon X-ray or β-irradiation. Instead, the color centers, Cl excitons, and oxygen defects are created and are stable at room temperature, and they might play a key role in the storage luminescence.
UR - http://www.scopus.com/inward/record.url?scp=21644486013&partnerID=8YFLogxK
U2 - 10.1021/jp050317r
DO - 10.1021/jp050317r
M3 - Article
C2 - 16852409
AN - SCOPUS:21644486013
SN - 1520-6106
VL - 109
SP - 11505
EP - 11511
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 23
ER -