Infrared microspectrometric characterizations and thermoluminescent properties for natural quartz slices

• Published in: BUNSEKI KAGAKU Vol. 51; no. 7; pp. 527 - 532
• Main Authors: HASHIMOTO, Tetsuo, YANAGAWA, Yuji, YAMAGUCHI, Takahiro
• Format: Journal Article
• Language: Japanese; English
• Published: Tokyo The Japan Society for Analytical Chemistry 01.07.2002; Japan Science and Technology Agency
• Subjects: Al-OH; color center images; hydroxyl group; mapping of impurities; microscopic infrared spectroscopy; natural quartz; thermoluminescence; thermoluminescence color images
• ISSN: 0525-1931
• DOI: 10.2116/bunsekikagaku.51.527

Blue thermoluminescence (BTL) phenomena from natural quartz have been attributed to the recombination of Al-hole centers with electrons released from trapped sites. The Al-impurity contents, however, inversely correlate with the BTL-intensity. To approach this interesting correlation, two kinds of quartz slice samples have been studied by the two-dimensional distribution of OH impurity: color center (CC) patterns and thermoluminescence color images (TLCI). Microscopically scanning infrared-spectroscopy showed the presence of Al-OH and Li dependent Al-OH species in natural quartz slices. Brazilian quartz gave a relatively homogeneous distribution of Al-OH as well as CC and BTL patterns. On the other hand, a Madagascan quartz slice offered heterogeneous growth patterns of Al-OH and Li-dependent Al-OH impurity contents, reflecting on unexpectedly inverse correlation of the CC and BTL distributions. These results suggest that mobile hydrogen atoms or hydrogen radicals, produced from the radiolysis of the Al-OH, could operate as a quencher of Al-hole centers for radiation-induced phenomena in quartz. The effects of the Al-hole center influenced by active hydrogen radicals were also confirmed from the difference of the Al-OH concentrations between room-temperature and liquid-nitrogen-temperature irradiations.