文献类型：期刊文献

中文题名：电气石晶体的光学吸收谱

英文题名：OPTICAL ABSORPTION SPECTRA OF TOURMALINE CRYSTALS

作者：范建良[1];冯锡淇[2];郭守国[1];刘学良[1]

机构：[1]华东理工大学材料科学与工程学院,上海200237;[2]中国科学院上海硅酸盐研究所,上海200050

年份：2009

卷号：37

期号：4

起止页码：523

中文期刊名：硅酸盐学报

外文期刊名：Journal of The Chinese Ceramic Society

收录：CSTPCD;;EI(收录号：20091912073317);Scopus;北大核心:【北大核心2008】；CSCD:【CSCD2011_2012】；

语种：中文

中文关键词：电气石;吸收光谱;退火;呈色机理;晶体结构

外文关键词：tourmaline; absorption spectroscopy; annealing; coloration mechanism; crystal structure

摘要：以新疆阿尔泰矿区的粉红色、绿色和褐绿色电气石晶体为研究对象,通过X射线荧光光谱仪、分光光度计分析了电气石的晶体结构,并对电气石晶体退火处理前后200～3300nm吸收光谱进行测定。结果表明:粉红色电气石的呈色与Mn3+的d电子跃迁有关,产生的吸收带有390,450nm和517nm;电气石的绿色调主要与交换耦合Fe3+-Fe3+离子对间的电荷转移形成的420nm吸收带和Fe2+-Fe3+离子对间的电荷转移形成的718nm吸收带有关;电气石晶体中,羟基伸缩振动(O-Hstr)引起的强吸收带在3800～3400cm-1,羟基与金属离子配位构成M-OH的伸缩和弯曲联合振动,在4800～4000cm-1产生5～6个吸收带,而羟基伸缩振动的第1倍频引起的吸收带则出现在7300～6700cm-1;在高温下,-(OH)(3)基团上的H+发生脱离,并与W晶格位置上的O2-发生键合形成-OH(1)基团。电气石晶体的结构式可简化表示为XY3Z6(Si6O18)(BO3)3(OH)3·(O2-,OH,F)。
Pink, green and brownish green tourmalines from the Altay deposit in Xinjiang, China were selected for this research. The crystal structure of the tourmaline and optical absorption spectra （200-3 300 nm） before and after annealing were analyzed by using ultraviolet-visible near infrared spectrometry. The results show that the pink color of tourmaline originates from the d-electron transition of Mn^3＋, which produces 390, 450 and 517 nm absorption bands; the green color is mainly attributed to charge transfers between exchange coupling Fe^3＋-Fe^3＋ ion pairs and Fe^2＋-Fe^3＋ ion pairs, which produce 420 and 718 nm strong absorption bands respectively. As for the absorption bands in the near infrared region, the bands in the range of 3 800-3 400 cm^-1 are attributed to hydroxyl stretching modes, the bands in the range of 7 300-6 800 cm^-1 are attributed to the first fundamental overtone of hydroxyl stretching modes. The bands in the range of 4 800-4 000 cm^-1 are attributed to the combination of stretching and bending modes of cationic hydroxyl units. H^＋ is divorced from the -OH（3） groups at high temperatures and then bonds with O^2- at the W-site, which generates new -OH groups. In addition, tourmaline crystal can be represented by the structural formula XYaZ6（Si6O18）（BO3）3（OH）3. （O^2-, OH, F）.