Abstract:At present, the application of infrared spectroscopy in the study of gem identification has been more concentrated in the mid-infrared range of 400~4 000 cm-1, and related research on the near-infrared region of the spectrum 4 000~10 000 cm-1 has been rarely done. This paperstudied the gemstones, jades and organic gems’ NIR spectroscopy by Fourier transform infrared spectrometer. The results showed that gem mineral’s NIR widespread presence of water absorption peak, whichwas mainly for different types of water combination tone and overtone, also can appear lower-energy electronic transition absorption peaks. 5 200 cm-1± was a combination tone of water molecules, and 7 000 cm-1± was a overtone of —OH while 5 898 and 7 849 cm-1± centered strong broad absorption band was a lower-energy electronic transition absorption peak. When there was only 7 000 cm-1± absorption peak, description that water in gem mineral only existed in the form of —OH. When there were 5 200 and 7 000 cm-1± absorption peaks at the same time, description that water existed in the form of molecules and —OH.The characteristics of organic gems were 5 200 cm-1± for the combination tone of NH stretching vibration and amide II and 7 000 cm-1± for the first overtone of NH stretching vibration. The near-infrared spectrum absorption peaks of different varieties of organic gems had different characteristics of position, shape and the relation strength. The characteristics of organic filling gems were 4 061, 4 683 cm-1± for the combination tone of benzene ring’s CH stretching vibration and bending vibration and 4 620, 4 683 cm-1± for the combination tone of CH stretching vibration and benzene ring skeleton vibration. The absorption peak associated with benzene ring, generally indicates that the sample through the fill process.
李晓静,虞 澜,祖恩东. 近红外光谱分析技术在宝石研究中的应用[J]. 光谱学与光谱分析, 2018, 38(01): 54-57.
LI Xiao-jing, YU Lan, ZU En-dong. Application of Near Infrared Spectroscopy in the Study of Gems. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2018, 38(01): 54-57.
[1] ZHANG Pei-li(张培莉). Systematic Gemmology(系统宝石学). Beijing: Geological Publishing House(北京: 地质出版社), 2006.
[2] WENG Shi-fu(翁诗甫). The Analysis of Fourier Transform Infrared Spectroscopy(傅里叶变换红外光谱分析). Beijing: Chemical Industry Press(北京: 化学工业出版社), 2010.
[3] Workman J. Practical Guide to Interpretive Near-Infrared Spectroscopy(近红外光谱解析实用指南). Translated by CHU Xiao-li, XU Yu-peng, TIAN Gao-you(褚小立,许育鹏,田高友,译). Beijing: Chemical Industry Press(北京: 化学工业出版社), 2009.
[4] ZHANG Liang, ZHOU Xia, LIU Wen-gang, et al(张 良, 周 霞, 刘文刚, 等). China Practical Medical(中国实用医药), 2013, 8(1): 251.
[5] Afara I O, Prasadam I, Crawford R, et al. Bone, 2013, 53: 350.
[6] Deak K, Szigedi T, Pek Z, et al. International Agrophysics, 2015, 29: 275.
[7] Camara-Martos F, Lopes J A, Moreno-Rojas R, et al. Society of Dairy Technology, 2015, 68(3): 357.
[8] LIAO Xiang, WANG Qing, FU Ji-hong, et al(廖 享, 王 青, 付继红, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2015, 35(9): 2526.