文献类型：期刊文献

中文题名：Study on low-temperature heat treatment of purplish red sapphire

英文题名：Study on low-temperature heat treatment of purplish red sapphire

作者：Xiaozhen Han[1,2];Yan Kang[3];Xiao Wu[2];Xueliang Liu[1];Shouguo Guo[1]

机构：[1]Gemstone Testing Center, East China University of Science & Technology, Shanghai 200237, China;[2]Jewelry College, Shanghai Jian Qiao University, Shanghai 201306, China;[3]Resea~rch Center of Analysis and Test, East China University of Science & Technology, Shanghai 200237, China

年份：2016

卷号：0

期号：5

起止页码：92

中文期刊名：中国光学快报：英文版

外文期刊名：Chinese Optics Letters

收录：CSTPCD;;Scopus;CSCD:【CSCD2015_2016】；

语种：英文

中文关键词：低温热处理;蓝宝石;紫红色;紫外-可见吸收光谱;X射线光电子能谱;加热过程;电荷转移;选择性吸收

外文关键词：Charge transfer;Electromagnetic wave absorption;Heat treatment;Low temperature operations;Sapphire;Temperature;Ultraviolet spectroscopy

摘要：A light purplish red sapphire is heat treated in an airtight crucible. The sample changes little in color after receiving heat treatment at 1100°C,but turns to light blue and blue after being treated at 1200°C and 1300°C,respectively. Before heating,the UV-VIS absorption spectra of the sample are dominated by the 551 nm broad absorption band contributed by the d-electron transition ~4A_2→~4T_2 of Cr~(3+). After heating,the UV-VIS absorption spectra are dominated by the 563 nm broad absorption band contributed by the intervalence charge transfer of Fe~(2+)-Ti~(4+). The x ray photoelectron spectroscopy test reveals that the Fe~(2+) and Ti~(4+) ion contents increase with increasing temperature. The sapphire changing from light purplish red to blue in the heating process is owing to the fact that the Fe~(2+) and Ti~(4+) contents grow and the intervalence charge transfer of Fe~(2+)-Ti~(4+) selectively absorbs UV-VIS light.
A light purplish red sapphire is heat treated in an airtight crucible. The sample changes little in color after receiving heat treatment at 1100℃, but turns to light blue and blue after being treated at 1200℃ and 1300℃, respectively. Before heating, the UV-VIS absorption spectra of the sample are dominated by the 551 nm broad absorption band contributed by the d-electron transition 4A2 →4 4T2 of Cr3＋. After heating, the UV-VIS absorption spectra are dominated by the 563 nm broad absorption band contributed by the inter- valence charge transfer of Fe2＋ - Ti4＋. The x ray photoelectron spectroscopy test reveals that the Fe2＋ and Ti4＋ ion contents increase with increasing temperature. The sapphire changing from light purplish red to blue in the heating process is owing to the fact that the Fe2＋ and Ti4＋ contents grow and the intervalence charge transfer of Fe2＋ - Ti4＋ selectively absorbs UV-VIS light.