TY - JOUR
T1 - TL in green tourmaline
T2 - Study of the centers responsible for the TL emission by EPR analysis
AU - Cano, Nilo F.
AU - Gundu Rao, T. K.
AU - Ayala Arenas, Jorge Sabino
AU - Gonzales-Lorenzo, Carlos D.
AU - Oliveira, Letícia M.
AU - Watanabe, Shigueo
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2019/1
Y1 - 2019/1
N2 - Electron paramagnetic resonance (EPR) studies have been carried out to identify the defect centers responsible for the thermoluminescence (TL) peaks in the mineral tourmaline. The mineral exhibits three TL peaks approximately at 170, 250 and 310 °C. The EPR spectrum of the green tourmaline sample pre-heated to 500 °C presented a large signal around g = 4.3 due to Fe3+ ion. Room temperature EPR spectrum of irradiated green tourmaline shows the formation of two defect centers in the region of g = 2.0. One of the centers (center II) with a g factor equal to 1.96 is identified as an F+-center and is related to the observed high temperature 250 and 310 °C TL peaks. Center I exhibiting a doublet is due to hydrogen atoms (H0), stable in the crystal lattice at room temperature and this center correlates with the TL peak at 170 °C of the green tourmaline. An optical absorption measurement also was carried out. Bands at around 430, 730 and 1100 nm have been observed.
AB - Electron paramagnetic resonance (EPR) studies have been carried out to identify the defect centers responsible for the thermoluminescence (TL) peaks in the mineral tourmaline. The mineral exhibits three TL peaks approximately at 170, 250 and 310 °C. The EPR spectrum of the green tourmaline sample pre-heated to 500 °C presented a large signal around g = 4.3 due to Fe3+ ion. Room temperature EPR spectrum of irradiated green tourmaline shows the formation of two defect centers in the region of g = 2.0. One of the centers (center II) with a g factor equal to 1.96 is identified as an F+-center and is related to the observed high temperature 250 and 310 °C TL peaks. Center I exhibiting a doublet is due to hydrogen atoms (H0), stable in the crystal lattice at room temperature and this center correlates with the TL peak at 170 °C of the green tourmaline. An optical absorption measurement also was carried out. Bands at around 430, 730 and 1100 nm have been observed.
KW - EPR
KW - Radiation dosimetry
KW - Silicate
KW - TL
KW - Tourmaline
UR - http://www.scopus.com/inward/record.url?scp=85053827921&partnerID=8YFLogxK
U2 - 10.1016/j.jlumin.2018.09.034
DO - 10.1016/j.jlumin.2018.09.034
M3 - Artículo
AN - SCOPUS:85053827921
VL - 205
SP - 324
EP - 328
JO - Journal of Luminescence
JF - Journal of Luminescence
SN - 0022-2313
ER -